TechDebt: Move BackendDict to base_backend (#5645)

moto/acm/models.py

@@ -1,8 +1,7 @@
 import base64
 import re
 import datetime
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto import settings
 from typing import Any, Dict, List, Iterable, Optional, Tuple, Set
 

moto/amp/models.py

@@ -1,7 +1,7 @@
 """PrometheusServiceBackend class with methods for supported APIs."""
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict, unix_time
+from moto.core.utils import unix_time
 from moto.moto_api._internal import mock_random
 from moto.utilities.paginator import paginate
 from moto.utilities.tagging_service import TaggingService

moto/apigateway/models.py

@@ -15,9 +15,9 @@ try:
 except ImportError:
     # OpenAPI Spec Validator < 0.5.0
     from openapi_spec_validator.exceptions import OpenAPIValidationError  # type: ignore
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
 from .utils import create_id, to_path
-from moto.core.utils import path_url, BackendDict
+from moto.core.utils import path_url
 from .exceptions import (
     ConflictException,
     DeploymentNotFoundException,

moto/apigatewayv2/models.py

@@ -3,8 +3,8 @@ import string
 import yaml
 from typing import Any, Dict, List, Optional
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict, unix_time
+from moto.core.utils import unix_time
 from moto.moto_api._internal import mock_random as random
 from moto.utilities.tagging_service import TaggingService
 

moto/applicationautoscaling/models.py

@@ -1,5 +1,4 @@
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.ecs import ecs_backends
 from moto.moto_api._internal import mock_random
 from .exceptions import AWSValidationException

moto/appsync/models.py

@@ -1,8 +1,8 @@
 import base64
 from datetime import timedelta, datetime, timezone
 from typing import Any, Dict, Iterable, List, Optional, Tuple
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict, unix_time
+from moto.core.utils import unix_time
 from moto.moto_api._internal import mock_random
 from moto.utilities.tagging_service import TaggingService
 

moto/athena/models.py

@@ -1,7 +1,6 @@
 import time
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.moto_api._internal import mock_random
 from typing import Any, Dict, List, Optional
 

moto/autoscaling/models.py

@@ -8,8 +8,8 @@ from moto.packages.boto.ec2.blockdevicemapping import (
 from moto.ec2.exceptions import InvalidInstanceIdError
 
 from collections import OrderedDict
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
-from moto.core.utils import camelcase_to_underscores, BackendDict
+from moto.core.utils import camelcase_to_underscores
 from moto.ec2 import ec2_backends
 from moto.ec2.models import EC2Backend
 from moto.ec2.models.instances import Instance
@@ -398,7 +398,7 @@ class FakeAutoScalingGroup(CloudFormationModel):
         load_balancers: List[str],
         target_group_arns: List[str],
         placement_group: str,
-        termination_policies: str,
+        termination_policies: List[str],
         autoscaling_backend: "AutoScalingBackend",
         ec2_backend: EC2Backend,
         tags: List[Dict[str, str]],
@@ -824,7 +824,7 @@ class AutoScalingBackend(BaseBackend):
         self.elbv2_backend: ELBv2Backend = elbv2_backends[self.account_id][region_name]
 
     @staticmethod
-    def default_vpc_endpoint_service(service_region: str, zones: List[Dict[str, Any]]) -> List[Dict[str, Any]]:  # type: ignore[misc]
+    def default_vpc_endpoint_service(service_region: str, zones: List[str]) -> List[Dict[str, Any]]:  # type: ignore[misc]
         """Default VPC endpoint service."""
         return BaseBackend.default_vpc_endpoint_service_factory(
             service_region, zones, "autoscaling"
@@ -980,7 +980,7 @@ class AutoScalingBackend(BaseBackend):
         load_balancers: List[str],
         target_group_arns: List[str],
         placement_group: str,
-        termination_policies: str,
+        termination_policies: List[str],
         tags: List[Dict[str, str]],
         capacity_rebalance: bool = False,
         new_instances_protected_from_scale_in: bool = False,
@@ -1223,7 +1223,7 @@ class AutoScalingBackend(BaseBackend):
         return lifecycle_hook
 
     def describe_lifecycle_hooks(
-        self, as_name: str, lifecycle_hook_names: Optional[str] = None
+        self, as_name: str, lifecycle_hook_names: Optional[List[str]] = None
     ) -> List[FakeLifeCycleHook]:
         return [
             lifecycle_hook

moto/autoscaling/responses.py

@@ -22,20 +22,20 @@ class AutoScalingResponse(BaseResponse):
             instance_monitoring = False
         params = self._get_params()
         self.autoscaling_backend.create_launch_configuration(
-            name=params.get("LaunchConfigurationName"),
+            name=params.get("LaunchConfigurationName"),  # type: ignore[arg-type]
-            image_id=params.get("ImageId"),
+            image_id=params.get("ImageId"),  # type: ignore[arg-type]
             key_name=params.get("KeyName"),
-            ramdisk_id=params.get("RamdiskId"),
+            ramdisk_id=params.get("RamdiskId"),  # type: ignore[arg-type]
-            kernel_id=params.get("KernelId"),
+            kernel_id=params.get("KernelId"),  # type: ignore[arg-type]
             security_groups=self._get_multi_param("SecurityGroups.member"),
-            user_data=params.get("UserData"),
+            user_data=params.get("UserData"),  # type: ignore[arg-type]
-            instance_type=params.get("InstanceType"),
+            instance_type=params.get("InstanceType"),  # type: ignore[arg-type]
             instance_monitoring=instance_monitoring,
             instance_profile_name=params.get("IamInstanceProfile"),
             spot_price=params.get("SpotPrice"),
-            ebs_optimized=params.get("EbsOptimized"),
+            ebs_optimized=params.get("EbsOptimized"),  # type: ignore[arg-type]
-            associate_public_ip_address=params.get("AssociatePublicIpAddress"),
+            associate_public_ip_address=params.get("AssociatePublicIpAddress"),  # type: ignore[arg-type]
-            block_device_mappings=params.get("BlockDeviceMappings"),
+            block_device_mappings=params.get("BlockDeviceMappings"),  # type: ignore[arg-type]
             instance_id=params.get("InstanceId"),
             metadata_options=params.get("MetadataOptions"),
             classic_link_vpc_id=params.get("ClassicLinkVPCId"),
@@ -311,17 +311,17 @@ class AutoScalingResponse(BaseResponse):
     def put_scaling_policy(self) -> str:
         params = self._get_params()
         policy = self.autoscaling_backend.put_scaling_policy(
-            name=params.get("PolicyName"),
+            name=params.get("PolicyName"),  # type: ignore[arg-type]
             policy_type=params.get("PolicyType", "SimpleScaling"),
-            metric_aggregation_type=params.get("MetricAggregationType"),
+            metric_aggregation_type=params.get("MetricAggregationType"),  # type: ignore[arg-type]
-            adjustment_type=params.get("AdjustmentType"),
+            adjustment_type=params.get("AdjustmentType"),  # type: ignore[arg-type]
-            as_name=params.get("AutoScalingGroupName"),
+            as_name=params.get("AutoScalingGroupName"),  # type: ignore[arg-type]
-            min_adjustment_magnitude=params.get("MinAdjustmentMagnitude"),
+            min_adjustment_magnitude=params.get("MinAdjustmentMagnitude"),  # type: ignore[arg-type]
             scaling_adjustment=self._get_int_param("ScalingAdjustment"),
             cooldown=self._get_int_param("Cooldown"),
             target_tracking_config=params.get("TargetTrackingConfiguration", {}),
             step_adjustments=params.get("StepAdjustments", []),
-            estimated_instance_warmup=params.get("EstimatedInstanceWarmup"),
+            estimated_instance_warmup=params.get("EstimatedInstanceWarmup"),  # type: ignore[arg-type]
             predictive_scaling_configuration=params.get(
                 "PredictiveScalingConfiguration", {}
             ),
@@ -480,7 +480,7 @@ class AutoScalingResponse(BaseResponse):
     def enable_metrics_collection(self) -> str:
         group_name = self._get_param("AutoScalingGroupName")
         metrics = self._get_params().get("Metrics")
-        self.autoscaling_backend.enable_metrics_collection(group_name, metrics)
+        self.autoscaling_backend.enable_metrics_collection(group_name, metrics)  # type: ignore[arg-type]
         template = self.response_template(ENABLE_METRICS_COLLECTION_TEMPLATE)
         return template.render()
 

moto/awslambda/models.py

@@ -23,9 +23,9 @@ import weakref
 import requests.exceptions
 
 from moto.awslambda.policy import Policy
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
 from moto.core.exceptions import RESTError
-from moto.core.utils import unix_time_millis, BackendDict
+from moto.core.utils import unix_time_millis
 from moto.iam.models import iam_backends
 from moto.iam.exceptions import IAMNotFoundException
 from moto.logs.models import logs_backends

moto/backends.py

@@ -1,7 +1,7 @@
 import importlib
 import moto
 import sys
-from moto.core.utils import BackendDict
+from moto.core import BackendDict
 from typing import Iterable, Tuple
 
 

moto/batch/models.py

@@ -9,7 +9,7 @@ import threading
 import dateutil.parser
 from sys import platform
 
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
 from moto.iam.models import iam_backends, IAMBackend
 from moto.ec2.models import ec2_backends, EC2Backend
 from moto.ec2.models.instances import Instance
@@ -28,7 +28,7 @@ from moto.ec2.exceptions import InvalidSubnetIdError
 from moto.ec2.models.instance_types import INSTANCE_TYPES as EC2_INSTANCE_TYPES
 from moto.ec2.models.instance_types import INSTANCE_FAMILIES as EC2_INSTANCE_FAMILIES
 from moto.iam.exceptions import IAMNotFoundException
-from moto.core.utils import unix_time_millis, BackendDict
+from moto.core.utils import unix_time_millis
 from moto.moto_api import state_manager
 from moto.moto_api._internal import mock_random
 from moto.moto_api._internal.managed_state_model import ManagedState

moto/batch_simple/models.py

@@ -5,7 +5,7 @@ from ..batch.models import (
     ClientException,
     BatchBackend,
 )
-from ..core.utils import BackendDict
+from ..core import BackendDict
 
 import datetime
 from typing import Any, Dict, List, Tuple, Optional

moto/budgets/models.py

@@ -1,8 +1,8 @@
 from collections import defaultdict
 from copy import deepcopy
 from datetime import datetime
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import unix_time, BackendDict
+from moto.core.utils import unix_time
 from typing import Any, Dict, Iterable, List
 from .exceptions import BudgetMissingLimit, DuplicateRecordException, NotFoundException
 

moto/ce/models.py

@@ -1,8 +1,7 @@
 """CostExplorerBackend class with methods for supported APIs."""
 
 from .exceptions import CostCategoryNotFound
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.utilities.tagging_service import TaggingService
 from moto.moto_api._internal import mock_random
 from typing import Any, Dict, List, Tuple

moto/cloudformation/models.py

@@ -7,11 +7,10 @@ from typing import Any, Dict, List, Optional, Iterable, Tuple, Union, Type
 from yaml.parser import ParserError  # pylint:disable=c-extension-no-member
 from yaml.scanner import ScannerError  # pylint:disable=c-extension-no-member
 
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
 from moto.core.utils import (
     iso_8601_datetime_with_milliseconds,
     iso_8601_datetime_without_milliseconds,
-    BackendDict,
 )
 from moto.moto_api._internal import mock_random
 from moto.sns.models import sns_backends
@@ -117,7 +116,7 @@ class FakeStackSet(BaseModel):
         self.execution_role = execution_role or self.execution_role
 
         if accounts and regions:
-            self.update_instances(accounts, regions, self.parameters)
+            self.update_instances(accounts, regions, self.parameters)  # type: ignore[arg-type]
 
         operation = self._create_operation(
             operation_id=operation_id,
@@ -158,7 +157,7 @@ class FakeStackSet(BaseModel):
         )
 
     def update_instances(
-        self, accounts: List[str], regions: List[str], parameters: Dict[str, str]
+        self, accounts: List[str], regions: List[str], parameters: List[Dict[str, Any]]
     ) -> Dict[str, Any]:
         operation_id = str(mock_random.uuid4())
 
@@ -208,7 +207,7 @@ class FakeStackInstances(BaseModel):
         self,
         accounts: List[str],
         regions: List[str],
-        parameters: Optional[Dict[str, str]],
+        parameters: Optional[List[Dict[str, Any]]],
     ) -> Any:
         for account in accounts:
             for region in regions:
@@ -655,7 +654,7 @@ class CloudFormationBackend(BaseBackend):
         stackset_name: str,
         accounts: List[str],
         regions: List[str],
-        parameters: Dict[str, str],
+        parameters: List[Dict[str, Any]],
     ) -> Dict[str, Any]:
         stack_set = self.get_stack_set(stackset_name)
         return stack_set.update_instances(accounts, regions, parameters)

moto/cloudfront/models.py

@@ -2,8 +2,8 @@ import string
 
 from datetime import datetime
 from typing import Any, Dict, Iterable, List, Tuple, Optional
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict, iso_8601_datetime_with_milliseconds
+from moto.core.utils import iso_8601_datetime_with_milliseconds
 from moto.moto_api import state_manager
 from moto.moto_api._internal.managed_state_model import ManagedState
 from moto.moto_api._internal import mock_random as random

moto/cloudtrail/models.py

@@ -3,8 +3,8 @@ import time
 
 from datetime import datetime
 from typing import Any, Dict, List, Optional, Iterable, Tuple
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import iso_8601_datetime_without_milliseconds, BackendDict
+from moto.core.utils import iso_8601_datetime_without_milliseconds
 from moto.utilities.tagging_service import TaggingService
 from .exceptions import (
     S3BucketDoesNotExistException,

moto/cloudwatch/models.py

@@ -1,11 +1,10 @@
 import json
 import statistics
 
-from moto.core import BaseBackend, BaseModel, CloudWatchMetricProvider
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudWatchMetricProvider
 from moto.core.utils import (
     iso_8601_datetime_without_milliseconds,
     iso_8601_datetime_with_nanoseconds,
-    BackendDict,
 )
 from moto.moto_api._internal import mock_random
 from datetime import datetime, timedelta

moto/codebuild/models.py

@@ -1,5 +1,5 @@
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import iso_8601_datetime_with_milliseconds, BackendDict
+from moto.core.utils import iso_8601_datetime_with_milliseconds
 from moto.moto_api._internal import mock_random
 from collections import defaultdict
 from dateutil import parser

moto/codecommit/models.py

@@ -1,5 +1,5 @@
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import iso_8601_datetime_with_milliseconds, BackendDict
+from moto.core.utils import iso_8601_datetime_with_milliseconds
 from moto.moto_api._internal import mock_random
 from datetime import datetime
 from typing import Dict, List, Optional

moto/codepipeline/models.py

@@ -1,7 +1,7 @@
 import json
 from datetime import datetime
 from typing import Any, Dict, List, Tuple
-from moto.core.utils import iso_8601_datetime_with_milliseconds, BackendDict
+from moto.core.utils import iso_8601_datetime_with_milliseconds
 from moto.iam.exceptions import IAMNotFoundException
 from moto.iam.models import iam_backends, IAMBackend
 
@@ -12,7 +12,7 @@ from moto.codepipeline.exceptions import (
     InvalidTagsException,
     TooManyTagsException,
 )
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
 
 
 class CodePipeline(BaseModel):

moto/cognitoidentity/models.py

@@ -4,8 +4,8 @@ import re
 
 from collections import OrderedDict
 from typing import Any, Dict, List, Optional
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import iso_8601_datetime_with_milliseconds, BackendDict
+from moto.core.utils import iso_8601_datetime_with_milliseconds
 from .exceptions import InvalidNameException, ResourceNotFoundError
 from .utils import get_random_identity_id
 

moto/cognitoidp/models.py

@@ -7,8 +7,7 @@ import enum
 from jose import jws
 from collections import OrderedDict
 from typing import Any, Dict, List, Tuple, Optional, Set
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.moto_api._internal import mock_random as random
 from .exceptions import (
     GroupExistsException,

moto/comprehend/models.py

@@ -1,7 +1,6 @@
 """ComprehendBackend class with methods for supported APIs."""
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.utilities.tagging_service import TaggingService
 from .exceptions import ResourceNotFound
 from typing import Any, Dict, List, Iterable

moto/config/models.py

@@ -48,10 +48,9 @@ from moto.config.exceptions import (
     MissingRequiredConfigRuleParameterException,
 )
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
 from moto.core.common_models import ConfigQueryModel
 from moto.core.responses import AWSServiceSpec
-from moto.core.utils import BackendDict
 from moto.iam.config import role_config_query, policy_config_query
 from moto.moto_api._internal import mock_random as random
 from moto.s3.config import s3_config_query
@@ -1382,7 +1381,7 @@ class ConfigBackend(BaseBackend):
         :param next_token:
         :return:
         """
-        identifiers = []
+        identifiers: List[Dict[str, Any]] = []
         new_token = None
 
         limit = limit or DEFAULT_PAGE_SIZE
@@ -1437,7 +1436,7 @@ class ConfigBackend(BaseBackend):
 
             resource_identifiers.append(item)
 
-        result = {"resourceIdentifiers": resource_identifiers}
+        result: Dict[str, Any] = {"resourceIdentifiers": resource_identifiers}
 
         if new_token:
             result["nextToken"] = new_token
@@ -1469,7 +1468,7 @@ class ConfigBackend(BaseBackend):
         if not self.config_aggregators.get(aggregator_name):
             raise NoSuchConfigurationAggregatorException()
 
-        identifiers = []
+        identifiers: List[Dict[str, Any]] = []
         new_token = None
         filters = filters or {}
 

moto/core/__init__.py

@@ -1,5 +1,5 @@
 from .models import DEFAULT_ACCOUNT_ID  # noqa
-from .base_backend import BaseBackend  # noqa
+from .base_backend import BaseBackend, BackendDict  # noqa
 from .common_models import BaseModel  # noqa
 from .common_models import CloudFormationModel, CloudWatchMetricProvider  # noqa
 from .models import patch_client, patch_resource  # noqa

moto/core/base_backend.py

@@ -1,15 +1,20 @@
+from boto3 import Session
 import re
 import string
 from collections import defaultdict
-from typing import List, Dict
+from functools import lru_cache
+from threading import RLock
+from typing import Any, List, Dict, Optional, ClassVar, TypeVar, Iterator
+from uuid import uuid4
+from moto.settings import allow_unknown_region
 from .utils import convert_regex_to_flask_path
 
 
-model_data = defaultdict(dict)
+model_data: Dict[str, Dict[str, object]] = defaultdict(dict)
 
 
 class InstanceTrackerMeta(type):
-    def __new__(meta, name, bases, dct):
+    def __new__(meta, name: str, bases: Any, dct: Dict[str, Any]) -> type:
         cls = super(InstanceTrackerMeta, meta).__new__(meta, name, bases, dct)
         if name == "BaseModel":
             return cls
@@ -17,30 +22,30 @@ class InstanceTrackerMeta(type):
         service = cls.__module__.split(".")[1]
         if name not in model_data[service]:
             model_data[service][name] = cls
-        cls.instances = []
+        cls.instances: ClassVar[List[Any]] = []  # type: ignore
         return cls
 
 
 class BaseBackend:
-    def __init__(self, region_name, account_id=None) -> None:
+    def __init__(self, region_name: str, account_id: str):
         self.region_name = region_name
         self.account_id = account_id
 
-    def _reset_model_refs(self):
+    def _reset_model_refs(self) -> None:
         # Remove all references to the models stored
         for models in model_data.values():
             for model in models.values():
-                model.instances = []
+                model.instances = []  # type: ignore[attr-defined]
 
     def reset(self) -> None:
         region_name = self.region_name
         account_id = self.account_id
         self._reset_model_refs()
         self.__dict__ = {}
-        self.__init__(region_name, account_id)
+        self.__init__(region_name, account_id)  # type: ignore[misc]
 
     @property
-    def _url_module(self):
+    def _url_module(self) -> Any:  # type: ignore[misc]
         backend_module = self.__class__.__module__
         backend_urls_module_name = backend_module.replace("models", "urls")
         backend_urls_module = __import__(
@@ -49,7 +54,7 @@ class BaseBackend:
         return backend_urls_module
 
     @property
-    def urls(self):
+    def urls(self) -> Dict[str, str]:
         """
         A dictionary of the urls to be mocked with this service and the handlers
         that should be called in their place
@@ -71,7 +76,7 @@ class BaseBackend:
         return urls
 
     @property
-    def url_paths(self):
+    def url_paths(self) -> Dict[str, str]:
         """
         A dictionary of the paths of the urls to be mocked with this service and
         the handlers that should be called in their place
@@ -86,14 +91,14 @@ class BaseBackend:
         return paths
 
     @property
-    def url_bases(self):
+    def url_bases(self) -> List[str]:
         """
         A list containing the url_bases extracted from urls.py
         """
         return self._url_module.url_bases
 
     @property
-    def flask_paths(self):
+    def flask_paths(self) -> Dict[str, str]:
         """
         The url paths that will be used for the flask server
         """
@@ -106,29 +111,29 @@ class BaseBackend:
 
     @staticmethod
     def default_vpc_endpoint_service(
-        service_region, zones
+        service_region: str, zones: List[str]  # pylint: disable=unused-argument
-    ):  # pylint: disable=unused-argument
+    ) -> List[Dict[str, str]]:
         """Invoke the factory method for any VPC endpoint(s) services."""
-        return None
+        return []
 
     @staticmethod
-    def vpce_random_number():
+    def vpce_random_number() -> str:
         from moto.moto_api._internal import mock_random as random
 
         """Return random number for a VPC endpoint service ID."""
         return "".join([random.choice(string.hexdigits.lower()) for i in range(17)])
 
     @staticmethod
-    def default_vpc_endpoint_service_factory(
+    def default_vpc_endpoint_service_factory(  # type: ignore[misc]
-        service_region,
+        service_region: str,
-        zones,
+        zones: List[str],
-        service="",
+        service: str = "",
-        service_type="Interface",
+        service_type: str = "Interface",
-        private_dns_names=True,
+        private_dns_names: bool = True,
-        special_service_name="",
+        special_service_name: str = "",
-        policy_supported=True,
+        policy_supported: bool = True,
-        base_endpoint_dns_names=None,
+        base_endpoint_dns_names: Optional[List[str]] = None,
-    ) -> List[Dict[str, str]]:  # pylint: disable=too-many-arguments
+    ) -> List[Dict[str, Any]]:  # pylint: disable=too-many-arguments
         """List of dicts representing default VPC endpoints for this service."""
         if special_service_name:
             service_name = f"com.amazonaws.{service_region}.{special_service_name}"
@@ -166,3 +171,148 @@ class BaseBackend:
     # def list_config_service_resources(self, resource_ids, resource_name, limit, next_token):
     #     """For AWS Config. This will list all of the resources of the given type and optional resource name and region"""
     #     raise NotImplementedError()
+
+
+backend_lock = RLock()
+SERVICE_BACKEND = TypeVar("SERVICE_BACKEND", bound=BaseBackend)
+
+
+class AccountSpecificBackend(Dict[str, SERVICE_BACKEND]):
+    """
+    Dictionary storing the data for a service in a specific account.
+    Data access pattern:
+      account_specific_backend[region: str] = backend: BaseBackend
+    """
+
+    def __init__(
+        self,
+        service_name: str,
+        account_id: str,
+        backend: type,
+        use_boto3_regions: bool,
+        additional_regions: Optional[List[str]],
+    ):
+        self.service_name = service_name
+        self.account_id = account_id
+        self.backend = backend
+        self.regions = []
+        if use_boto3_regions:
+            sess = Session()
+            self.regions.extend(sess.get_available_regions(service_name))
+            self.regions.extend(
+                sess.get_available_regions(service_name, partition_name="aws-us-gov")
+            )
+            self.regions.extend(
+                sess.get_available_regions(service_name, partition_name="aws-cn")
+            )
+        self.regions.extend(additional_regions or [])
+        self._id = str(uuid4())
+
+    def __hash__(self) -> int:  # type: ignore[override]
+        return hash(self._id)
+
+    def __eq__(self, other: Any) -> bool:
+        return (
+            other
+            and isinstance(other, AccountSpecificBackend)
+            and other._id == self._id
+        )
+
+    def __ne__(self, other: Any) -> bool:
+        return not self.__eq__(other)
+
+    def reset(self) -> None:
+        for region_specific_backend in self.values():
+            region_specific_backend.reset()
+
+    def __contains__(self, region: str) -> bool:  # type: ignore[override]
+        return region in self.regions or region in self.keys()
+
+    def __delitem__(self, key: str) -> None:
+        super().__delitem__(key)
+
+    def __iter__(self) -> Iterator[str]:
+        return super().__iter__()
+
+    def __len__(self) -> int:
+        return super().__len__()
+
+    def __setitem__(self, key: str, value: SERVICE_BACKEND) -> None:
+        super().__setitem__(key, value)
+
+    @lru_cache()
+    def __getitem__(self, region_name: str) -> SERVICE_BACKEND:  # type: ignore[override]
+        if region_name in self.keys():
+            return super().__getitem__(region_name)
+        # Create the backend for a specific region
+        with backend_lock:
+            if region_name in self.regions and region_name not in self.keys():
+                super().__setitem__(
+                    region_name, self.backend(region_name, account_id=self.account_id)
+                )
+            if region_name not in self.regions and allow_unknown_region():
+                super().__setitem__(
+                    region_name, self.backend(region_name, account_id=self.account_id)
+                )
+        return super().__getitem__(region_name)
+
+
+class BackendDict(Dict[str, AccountSpecificBackend]):  # type: ignore[type-arg]
+    """
+    Data Structure to store everything related to a specific service.
+    Format:
+      [account_id: str]: AccountSpecificBackend
+      [account_id: str][region: str] = BaseBackend
+    """
+
+    def __init__(
+        self,
+        backend: Any,
+        service_name: str,
+        use_boto3_regions: bool = True,
+        additional_regions: Optional[List[str]] = None,
+    ):
+        self.backend = backend
+        self.service_name = service_name
+        self._use_boto3_regions = use_boto3_regions
+        self._additional_regions = additional_regions
+        self._id = str(uuid4())
+
+    def __hash__(self) -> int:  # type: ignore[override]
+        # Required for the LRUcache to work.
+        # service_name is enough to determine uniqueness - other properties are dependent
+        return hash(self._id)
+
+    def __eq__(self, other: Any) -> bool:
+        return other and isinstance(other, BackendDict) and other._id == self._id
+
+    def __ne__(self, other: Any) -> bool:
+        return not self.__eq__(other)
+
+    @lru_cache()
+    def __getitem__(self, account_id: str) -> AccountSpecificBackend:  # type: ignore
+        self._create_account_specific_backend(account_id)
+        return super().__getitem__(account_id)
+
+    def __delitem__(self, key: str) -> None:
+        super().__delitem__(key)
+
+    def __iter__(self) -> Iterator[str]:
+        return super().__iter__()
+
+    def __len__(self) -> int:
+        return super().__len__()
+
+    def __setitem__(self, key: str, value: AccountSpecificBackend) -> None:  # type: ignore[type-arg]
+        super().__setitem__(key, value)
+
+    def _create_account_specific_backend(self, account_id: str) -> None:
+        with backend_lock:
+            if account_id not in list(self.keys()):
+                self[account_id] = AccountSpecificBackend(
+                    service_name=self.service_name,
+                    account_id=account_id,
+                    backend=self.backend,
+                    use_boto3_regions=self._use_boto3_regions,
+                    additional_regions=self._additional_regions,
+                )

moto/core/models.py

@@ -14,7 +14,7 @@ from botocore.config import Config
 from botocore.handlers import BUILTIN_HANDLERS
 
 from moto import settings
-from moto.core.utils import BackendDict
+from moto.core.base_backend import BackendDict
 from .botocore_stubber import BotocoreStubber
 from .custom_responses_mock import (
     get_response_mock,

moto/core/utils.py

@@ -1,15 +1,9 @@
-from functools import lru_cache
-
 import datetime
 import inspect
 import re
 from botocore.exceptions import ClientError
-from boto3 import Session
+from typing import Optional
-from moto.settings import allow_unknown_region
-from threading import RLock
-from typing import Any, Optional, List
 from urllib.parse import urlparse
-from uuid import uuid4
 
 
 def camelcase_to_underscores(argument: Optional[str]) -> str:
@@ -69,7 +63,7 @@ def method_names_from_class(clazz):
     return [x[0] for x in inspect.getmembers(clazz, predicate=predicate)]
 
 
-def convert_regex_to_flask_path(url_path):
+def convert_regex_to_flask_path(url_path: str) -> str:
     """
     Converts a regex matching url to one that can be used with flask
     """
@@ -308,118 +302,3 @@ def extract_region_from_aws_authorization(string):
     if region == auth:
         return None
     return region
-
-
-backend_lock = RLock()
-
-
-class AccountSpecificBackend(dict):
-    """
-    Dictionary storing the data for a service in a specific account.
-    Data access pattern:
-      account_specific_backend[region: str] = backend: BaseBackend
-    """
-
-    def __init__(
-        self, service_name, account_id, backend, use_boto3_regions, additional_regions
-    ):
-        self.service_name = service_name
-        self.account_id = account_id
-        self.backend = backend
-        self.regions = []
-        if use_boto3_regions:
-            sess = Session()
-            self.regions.extend(sess.get_available_regions(service_name))
-            self.regions.extend(
-                sess.get_available_regions(service_name, partition_name="aws-us-gov")
-            )
-            self.regions.extend(
-                sess.get_available_regions(service_name, partition_name="aws-cn")
-            )
-        self.regions.extend(additional_regions or [])
-        self._id = str(uuid4())
-
-    def __hash__(self):
-        return hash(self._id)
-
-    def __eq__(self, other):
-        return (
-            other
-            and isinstance(other, AccountSpecificBackend)
-            and other._id == self._id
-        )
-
-    def __ne__(self, other):
-        return not self.__eq__(other)
-
-    def reset(self):
-        for region_specific_backend in self.values():
-            region_specific_backend.reset()
-
-    def __contains__(self, region):
-        return region in self.regions or region in self.keys()
-
-    @lru_cache()
-    def __getitem__(self, region_name):
-        if region_name in self.keys():
-            return super().__getitem__(region_name)
-        # Create the backend for a specific region
-        with backend_lock:
-            if region_name in self.regions and region_name not in self.keys():
-                super().__setitem__(
-                    region_name, self.backend(region_name, account_id=self.account_id)
-                )
-            if region_name not in self.regions and allow_unknown_region():
-                super().__setitem__(
-                    region_name, self.backend(region_name, account_id=self.account_id)
-                )
-        return super().__getitem__(region_name)
-
-
-class BackendDict(dict):
-    """
-    Data Structure to store everything related to a specific service.
-    Format:
-      [account_id: str]: AccountSpecificBackend
-      [account_id: str][region: str] = BaseBackend
-    """
-
-    def __init__(
-        self,
-        backend: Any,
-        service_name: str,
-        use_boto3_regions: bool = True,
-        additional_regions: Optional[List[str]] = None,
-    ):
-        self.backend = backend
-        self.service_name = service_name
-        self._use_boto3_regions = use_boto3_regions
-        self._additional_regions = additional_regions
-        self._id = str(uuid4())
-
-    def __hash__(self):
-        # Required for the LRUcache to work.
-        # service_name is enough to determine uniqueness - other properties are dependent
-        return hash(self._id)
-
-    def __eq__(self, other):
-        return other and isinstance(other, BackendDict) and other._id == self._id
-
-    def __ne__(self, other):
-        return not self.__eq__(other)
-
-    @lru_cache()
-    def __getitem__(self, account_id) -> AccountSpecificBackend:
-        self._create_account_specific_backend(account_id)
-        return super().__getitem__(account_id)
-
-    def _create_account_specific_backend(self, account_id) -> None:
-        with backend_lock:
-            if account_id not in self.keys():
-                self[account_id] = AccountSpecificBackend(
-                    service_name=self.service_name,
-                    account_id=account_id,
-                    backend=self.backend,
-                    use_boto3_regions=self._use_boto3_regions,
-                    additional_regions=self._additional_regions,
-                )

moto/databrew/models.py

@@ -6,8 +6,7 @@ from copy import deepcopy
 import math
 from datetime import datetime
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.core.utils import underscores_to_camelcase
 from moto.core.utils import camelcase_to_pascal
 

moto/datapipeline/models.py

@@ -1,8 +1,7 @@
 import datetime
 
 from collections import OrderedDict
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
-from moto.core.utils import BackendDict
 from .utils import get_random_pipeline_id, remove_capitalization_of_dict_keys
 
 

moto/datasync/models.py

@@ -1,6 +1,5 @@
 from collections import OrderedDict
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 
 from .exceptions import InvalidRequestException
 

moto/dax/models.py

@@ -1,6 +1,6 @@
 """DAXBackend class with methods for supported APIs."""
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict, unix_time
+from moto.core.utils import unix_time
 from moto.moto_api import state_manager
 from moto.moto_api._internal import mock_random as random
 from moto.moto_api._internal.managed_state_model import ManagedState

moto/dms/models.py

@@ -1,8 +1,7 @@
 import json
 
 from datetime import datetime
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 
 from .exceptions import (
     InvalidResourceStateFault,

moto/ds/models.py

@@ -1,8 +1,7 @@
 """DirectoryServiceBackend class with methods for supported APIs."""
 from datetime import datetime, timezone
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.ds.exceptions import (
     ClientException,
     DirectoryLimitExceededException,

moto/dynamodb/models/__init__.py

@@ -6,8 +6,8 @@ import json
 import re
 
 from collections import OrderedDict
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
-from moto.core.utils import unix_time, unix_time_millis, BackendDict
+from moto.core.utils import unix_time, unix_time_millis
 from moto.core.exceptions import JsonRESTError
 from moto.dynamodb.comparisons import get_filter_expression
 from moto.dynamodb.comparisons import get_expected

moto/dynamodb_v20111205/models.py

@@ -3,8 +3,8 @@ import datetime
 import json
 
 from collections import OrderedDict
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
-from moto.core.utils import unix_time, BackendDict
+from moto.core.utils import unix_time
 from .comparisons import get_comparison_func
 
 

moto/dynamodbstreams/models.py

@@ -2,8 +2,7 @@ import os
 import json
 import base64
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.dynamodb.models import dynamodb_backends, DynamoJsonEncoder
 
 

moto/ebs/models.py

@@ -1,7 +1,7 @@
 """EBSBackend class with methods for supported APIs."""
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict, unix_time
+from moto.core.utils import unix_time
 from moto.ec2 import ec2_backends
 from moto.ec2.models.elastic_block_store import Snapshot
 from moto.moto_api._internal import mock_random

moto/ec2/models/__init__.py

@@ -1,5 +1,4 @@
-from moto.core import BaseBackend
+from moto.core import BaseBackend, BackendDict
-from moto.core.utils import BackendDict
 from ..exceptions import (
     EC2ClientError,
     InvalidID,

moto/ec2instanceconnect/models.py

@@ -1,6 +1,5 @@
 import json
-from moto.core import BaseBackend
+from moto.core import BaseBackend, BackendDict
-from moto.core.utils import BackendDict
 
 
 class Ec2InstanceConnectBackend(BaseBackend):

moto/ecr/models.py

@@ -7,8 +7,8 @@ from typing import Dict, List
 
 from botocore.exceptions import ParamValidationError
 
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
-from moto.core.utils import iso_8601_datetime_without_milliseconds, BackendDict
+from moto.core.utils import iso_8601_datetime_without_milliseconds
 from moto.ecr.exceptions import (
     ImageNotFoundException,
     RepositoryNotFoundException,

moto/ecs/models.py

@@ -5,14 +5,9 @@ from typing import Any
 import pytz
 
 from moto import settings
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
 from moto.core.exceptions import JsonRESTError
-from moto.core.utils import (
+from moto.core.utils import unix_time, pascal_to_camelcase, remap_nested_keys
-    unix_time,
-    pascal_to_camelcase,
-    remap_nested_keys,
-    BackendDict,
-)
 
 from ..ec2.utils import random_private_ip
 from moto.ec2 import ec2_backends

moto/efs/models.py

@@ -8,12 +8,8 @@ import json
 import time
 from copy import deepcopy
 
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
-from moto.core.utils import (
+from moto.core.utils import camelcase_to_underscores, underscores_to_camelcase
-    camelcase_to_underscores,
-    underscores_to_camelcase,
-    BackendDict,
-)
 from moto.ec2 import ec2_backends
 from moto.ec2.exceptions import InvalidSubnetIdError
 from moto.efs.exceptions import (

moto/eks/models.py

@@ -1,7 +1,7 @@
 from datetime import datetime
 
-from moto.core import BaseBackend
+from moto.core import BaseBackend, BackendDict
-from moto.core.utils import iso_8601_datetime_without_milliseconds, BackendDict
+from moto.core.utils import iso_8601_datetime_without_milliseconds
 from moto.moto_api._internal import mock_random as random
 
 from .exceptions import (

moto/elasticache/models.py

@@ -1,5 +1,4 @@
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 
 from .exceptions import UserAlreadyExists, UserNotFound
 

moto/elasticbeanstalk/models.py

@@ -1,7 +1,6 @@
 import weakref
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from .exceptions import InvalidParameterValueError, ResourceNotFoundException
 from .utils import make_arn
 

moto/elastictranscoder/models.py

@@ -1,5 +1,4 @@
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.moto_api._internal import mock_random as random
 import string
 

moto/elb/models.py

@@ -3,8 +3,7 @@ import pytz
 from collections import OrderedDict
 from typing import List, Iterable
 
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
-from moto.core.utils import BackendDict
 from moto.ec2.models import ec2_backends
 from moto.ec2.exceptions import InvalidInstanceIdError
 from moto.moto_api._internal import mock_random

moto/elbv2/models.py

@@ -5,11 +5,8 @@ from botocore.exceptions import ParamValidationError
 from collections import OrderedDict
 from typing import Any, List, Dict, Iterable, Optional
 from moto.core.exceptions import RESTError
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
-from moto.core.utils import (
+from moto.core.utils import iso_8601_datetime_with_milliseconds
-    iso_8601_datetime_with_milliseconds,
-    BackendDict,
-)
 from moto.ec2.models import ec2_backends
 from moto.moto_api._internal import mock_random
 from moto.utilities.tagging_service import TaggingService

moto/emr/models.py

@@ -5,8 +5,7 @@ import warnings
 
 import pytz
 from dateutil.parser import parse as dtparse
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.emr.exceptions import (
     InvalidRequestException,
     ValidationException,

moto/emrcontainers/models.py

@@ -2,8 +2,8 @@
 import re
 from datetime import datetime
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import iso_8601_datetime_without_milliseconds, BackendDict
+from moto.core.utils import iso_8601_datetime_without_milliseconds
 
 from .utils import random_cluster_id, random_job_id, get_partition, paginated_list
 from .exceptions import ResourceNotFoundException

moto/emrserverless/models.py

@@ -3,8 +3,8 @@ import re
 from datetime import datetime
 import inspect
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict, iso_8601_datetime_without_milliseconds
+from moto.core.utils import iso_8601_datetime_without_milliseconds
 from .utils import (
     default_auto_start_configuration,
     default_auto_stop_configuration,

moto/es/models.py

@@ -1,5 +1,4 @@
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.moto_api._internal import mock_random
 from .exceptions import DomainNotFound
 

moto/events/models.py

@@ -12,12 +12,11 @@ from operator import lt, le, eq, ge, gt
 
 from collections import OrderedDict
 from moto.core.exceptions import JsonRESTError
-from moto.core import BaseBackend, CloudFormationModel, BaseModel
+from moto.core import BaseBackend, BackendDict, CloudFormationModel, BaseModel
 from moto.core.utils import (
     unix_time,
     unix_time_millis,
     iso_8601_datetime_without_milliseconds,
-    BackendDict,
 )
 from moto.events.exceptions import (
     ValidationException,

moto/firehose/models.py

@@ -25,8 +25,7 @@ import warnings
 
 import requests
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.firehose.exceptions import (
     ConcurrentModificationException,
     InvalidArgumentException,

moto/forecast/models.py

@@ -1,8 +1,8 @@
 import re
 from datetime import datetime
 
-from moto.core import BaseBackend
+from moto.core import BaseBackend, BackendDict
-from moto.core.utils import iso_8601_datetime_without_milliseconds, BackendDict
+from moto.core.utils import iso_8601_datetime_without_milliseconds
 from .exceptions import (
     InvalidInputException,
     ResourceAlreadyExistsException,

moto/glacier/models.py

@@ -2,8 +2,7 @@ import hashlib
 
 import datetime
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.utilities.utils import md5_hash
 
 from .utils import get_job_id

moto/glue/models.py

@@ -4,8 +4,7 @@ from datetime import datetime
 import re
 from typing import List
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.moto_api import state_manager
 from moto.moto_api._internal import mock_random
 from moto.moto_api._internal.managed_state_model import ManagedState

moto/greengrass/models.py

@@ -3,8 +3,8 @@ from collections import OrderedDict
 from datetime import datetime
 import re
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict, iso_8601_datetime_with_milliseconds
+from moto.core.utils import iso_8601_datetime_with_milliseconds
 from moto.moto_api._internal import mock_random
 from .exceptions import (
     GreengrassClientError,

moto/guardduty/models.py

@@ -1,6 +1,5 @@
 from __future__ import unicode_literals
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.moto_api._internal import mock_random
 from datetime import datetime
 

moto/iam/models.py

@@ -13,11 +13,16 @@ from jinja2 import Template
 from typing import List, Mapping
 from urllib import parse
 from moto.core.exceptions import RESTError
-from moto.core import DEFAULT_ACCOUNT_ID, BaseBackend, BaseModel, CloudFormationModel
+from moto.core import (
+    DEFAULT_ACCOUNT_ID,
+    BaseBackend,
+    BaseModel,
+    CloudFormationModel,
+    BackendDict,
+)
 from moto.core.utils import (
     iso_8601_datetime_without_milliseconds,
     iso_8601_datetime_with_milliseconds,
-    BackendDict,
     unix_time,
 )
 from moto.iam.policy_validation import (
@@ -64,14 +69,16 @@ SERVICE_NAME_CONVERSION = {
 }
 
 
-def get_account_id_from(access_key):
+def get_account_id_from(access_key: str) -> str:
     for account_id, account in iam_backends.items():
         if access_key in account["global"].access_keys:
             return account_id
     return DEFAULT_ACCOUNT_ID
 
 
-def mark_account_as_visited(account_id, access_key, service, region):
+def mark_account_as_visited(
+    account_id: str, access_key: str, service: str, region: str
+) -> None:
     account = iam_backends[account_id]
     if access_key in account["global"].access_keys:
         account["global"].access_keys[access_key].last_used = AccessKeyLastUsed(
@@ -3050,6 +3057,6 @@ class IAMBackend(BaseBackend):
         return True
 
 
-iam_backends: Mapping[str, Mapping[str, IAMBackend]] = BackendDict(
+iam_backends = BackendDict(
     IAMBackend, "iam", use_boto3_regions=False, additional_regions=["global"]
 )

moto/instance_metadata/models.py

@@ -1,5 +1,4 @@
-from moto.core import BaseBackend
+from moto.core import BaseBackend, BackendDict
-from moto.core.utils import BackendDict
 
 
 class InstanceMetadataBackend(BaseBackend):

moto/iot/models.py

@@ -11,8 +11,7 @@ from datetime import datetime, timedelta
 
 from .utils import PAGINATION_MODEL
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.moto_api._internal import mock_random as random
 from moto.utilities.paginator import paginate
 from .exceptions import (

moto/iotdata/models.py

@@ -2,8 +2,8 @@ import json
 import time
 import jsondiff
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import merge_dicts, BackendDict
+from moto.core.utils import merge_dicts
 from moto.iot import iot_backends
 from .exceptions import (
     ConflictException,

moto/kinesis/models.py

@@ -5,8 +5,8 @@ import itertools
 
 from operator import attrgetter
 
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
-from moto.core.utils import unix_time, BackendDict
+from moto.core.utils import unix_time
 from moto.utilities.paginator import paginate
 from moto.utilities.utils import md5_hash
 from .exceptions import (

moto/kinesisvideo/models.py

@@ -1,7 +1,6 @@
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
 from datetime import datetime
 from .exceptions import ResourceNotFoundException, ResourceInUseException
-from moto.core.utils import BackendDict
 from moto.moto_api._internal import mock_random as random
 
 

moto/kinesisvideoarchivedmedia/models.py

@@ -1,5 +1,4 @@
-from moto.core import BaseBackend
+from moto.core import BaseBackend, BackendDict
-from moto.core.utils import BackendDict
 from moto.kinesisvideo import kinesisvideo_backends
 from moto.sts.utils import random_session_token
 

moto/kms/models.py

@@ -8,8 +8,8 @@ from cryptography.hazmat.primitives import hashes
 
 from cryptography.hazmat.primitives.asymmetric import padding
 
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
-from moto.core.utils import unix_time, BackendDict
+from moto.core.utils import unix_time
 from moto.moto_api._internal import mock_random
 from moto.utilities.tagging_service import TaggingService
 from moto.core.exceptions import JsonRESTError

moto/logs/models.py

@@ -1,8 +1,8 @@
 from datetime import datetime, timedelta
 from typing import Any, Dict, List, Tuple, Optional
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
 from moto.core import CloudFormationModel
-from moto.core.utils import unix_time_millis, BackendDict
+from moto.core.utils import unix_time_millis
 from moto.logs.metric_filters import MetricFilters
 from moto.logs.exceptions import (
     ResourceNotFoundException,

moto/managedblockchain/models.py

@@ -3,8 +3,7 @@ from __future__ import division
 import datetime
 import re
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 
 from .exceptions import (
     BadRequestException,

moto/mediaconnect/models.py

@@ -1,7 +1,6 @@
 from collections import OrderedDict
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.mediaconnect.exceptions import NotFoundException
 from moto.moto_api._internal import mock_random as random
 

moto/medialive/models.py

@@ -1,7 +1,6 @@
 from collections import OrderedDict
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.moto_api._internal import mock_random
 
 

moto/mediapackage/models.py

@@ -1,7 +1,6 @@
 from collections import OrderedDict
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 
 from .exceptions import ClientError
 

moto/mediastore/models.py

@@ -1,8 +1,7 @@
 from collections import OrderedDict
 from datetime import date
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from .exceptions import (
     ContainerNotFoundException,
     ResourceNotFoundException,

moto/mediastoredata/models.py

@@ -1,8 +1,7 @@
 import hashlib
 from collections import OrderedDict
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from .exceptions import ClientError
 
 

moto/meteringmarketplace/models.py

@@ -1,7 +1,6 @@
 import collections
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
 from moto.moto_api._internal import mock_random
-from moto.core.utils import BackendDict
 
 
 class UsageRecord(BaseModel, dict):

moto/moto_api/_internal/models.py

@@ -1,4 +1,4 @@
-from moto.core import BaseBackend
+from moto.core import BaseBackend, DEFAULT_ACCOUNT_ID
 
 
 class MotoAPIBackend(BaseBackend):
@@ -31,4 +31,4 @@ class MotoAPIBackend(BaseBackend):
         state_manager.unset_transition(model_name)
 
 
-moto_api_backend = MotoAPIBackend(region_name="global")
+moto_api_backend = MotoAPIBackend(region_name="global", account_id=DEFAULT_ACCOUNT_ID)

moto/moto_api/_internal/recorder/models.py

@@ -5,6 +5,7 @@ import os
 
 import requests
 from botocore.awsrequest import AWSPreparedRequest
+from typing import Any, Optional
 from urllib.parse import urlparse
 
 
@@ -14,7 +15,7 @@ class Recorder:
         self._os_enabled = bool(os.environ.get("MOTO_ENABLE_RECORDING", False))
         self._user_enabled = self._os_enabled
 
-    def _record_request(self, request, body=None):
+    def _record_request(self, request: Any, body: Optional[bytes] = None) -> None:
         """
         Record the current request
         """

moto/moto_server/werkzeug_app.py

@@ -16,8 +16,8 @@ except ImportError:
 
 import moto.backends as backends
 import moto.backend_index as backend_index
-from moto.core import DEFAULT_ACCOUNT_ID
+from moto.core import BackendDict, DEFAULT_ACCOUNT_ID
-from moto.core.utils import convert_to_flask_response, BackendDict
+from moto.core.utils import convert_to_flask_response
 
 from .utilities import AWSTestHelper, RegexConverter
 

moto/mq/models.py

@@ -1,8 +1,8 @@
 import base64
 import xmltodict
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict, unix_time
+from moto.core.utils import unix_time
 from moto.moto_api._internal import mock_random
 from moto.utilities.tagging_service import TaggingService
 

moto/opsworks/models.py

@@ -1,6 +1,5 @@
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
 from moto.ec2 import ec2_backends
-from moto.core.utils import BackendDict
 from moto.moto_api._internal import mock_random as random
 import datetime
 

moto/organizations/models.py

@@ -2,9 +2,9 @@ import datetime
 import re
 import json
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
 from moto.core.exceptions import RESTError
-from moto.core.utils import unix_time, BackendDict
+from moto.core.utils import unix_time
 from moto.organizations import utils
 from moto.organizations.exceptions import (
     InvalidInputException,

moto/personalize/models.py

@@ -1,8 +1,8 @@
 """PersonalizeBackend class with methods for supported APIs."""
 
 from .exceptions import ResourceNotFoundException
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict, unix_time
+from moto.core.utils import unix_time
 
 
 class Schema(BaseModel):

moto/pinpoint/models.py

@@ -1,6 +1,6 @@
 from datetime import datetime
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict, unix_time
+from moto.core.utils import unix_time
 from moto.moto_api._internal import mock_random
 from moto.utilities.tagging_service import TaggingService
 

moto/polly/models.py

@@ -1,8 +1,7 @@
 from xml.etree import ElementTree as ET
 import datetime
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 
 from .resources import VOICE_DATA
 from .utils import make_arn_for_lexicon

moto/quicksight/models.py

@@ -1,7 +1,6 @@
 """QuickSightBackend class with methods for supported APIs."""
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from .exceptions import ResourceNotFoundException
 
 

moto/ram/models.py

@@ -2,8 +2,8 @@ import re
 import string
 from datetime import datetime
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import unix_time, BackendDict
+from moto.core.utils import unix_time
 from moto.moto_api._internal import mock_random as random
 from moto.organizations import organizations_backends
 from moto.ram.exceptions import (

moto/rds/models.py

@@ -7,8 +7,8 @@ from collections import defaultdict
 from jinja2 import Template
 from re import compile as re_compile
 from collections import OrderedDict
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
-from moto.core.utils import iso_8601_datetime_with_milliseconds, BackendDict
+from moto.core.utils import iso_8601_datetime_with_milliseconds
 from moto.ec2.models import ec2_backends
 from moto.moto_api._internal import mock_random as random
 from .exceptions import (

moto/redshift/models.py

@@ -2,8 +2,8 @@ import copy
 import datetime
 
 from collections import OrderedDict
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
-from moto.core.utils import iso_8601_datetime_with_milliseconds, BackendDict
+from moto.core.utils import iso_8601_datetime_with_milliseconds
 from moto.ec2 import ec2_backends
 from moto.moto_api._internal import mock_random
 from .exceptions import (

moto/redshiftdata/models.py

@@ -1,8 +1,8 @@
 import re
 from datetime import datetime
 
-from moto.core import BaseBackend
+from moto.core import BaseBackend, BackendDict
-from moto.core.utils import BackendDict, iso_8601_datetime_without_milliseconds
+from moto.core.utils import iso_8601_datetime_without_milliseconds
 from moto.moto_api._internal import mock_random as random
 from moto.redshiftdata.exceptions import ValidationException, ResourceNotFoundException
 

moto/rekognition/models.py

@@ -2,8 +2,7 @@
 
 import string
 
-from moto.core import BaseBackend
+from moto.core import BaseBackend, BackendDict
-from moto.core.utils import BackendDict
 from moto.moto_api._internal import mock_random as random
 
 

moto/resourcegroups/models.py

@@ -3,8 +3,7 @@ from builtins import str
 import json
 import re
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from .exceptions import BadRequestException
 
 

moto/resourcegroupstaggingapi/models.py

@@ -1,6 +1,5 @@
-from moto.core import BaseBackend
+from moto.core import BaseBackend, BackendDict
 from moto.core.exceptions import RESTError
-from moto.core.utils import BackendDict
 from moto.moto_api._internal import mock_random
 
 from moto.s3 import s3_backends

moto/route53/models.py

@@ -18,8 +18,7 @@ from moto.route53.exceptions import (
     PublicZoneVPCAssociation,
     QueryLoggingConfigAlreadyExists,
 )
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
-from moto.core.utils import BackendDict
 from moto.moto_api._internal import mock_random as random
 from moto.utilities.paginator import paginate
 from .utils import PAGINATION_MODEL

moto/route53resolver/models.py

@@ -4,8 +4,7 @@ from datetime import datetime, timezone
 from ipaddress import ip_address, ip_network, IPv4Address
 import re
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.ec2 import ec2_backends
 from moto.ec2.exceptions import InvalidSubnetIdError
 from moto.ec2.exceptions import InvalidSecurityGroupNotFoundError

moto/s3/models.py

@@ -14,14 +14,13 @@ import urllib.parse
 
 from bisect import insort
 from importlib import reload
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BaseModel, BackendDict, CloudFormationModel
 from moto.core import CloudWatchMetricProvider
 from moto.core.utils import (
     iso_8601_datetime_without_milliseconds_s3,
     rfc_1123_datetime,
     unix_time,
     unix_time_millis,
-    BackendDict,
 )
 from moto.cloudwatch.models import MetricDatum
 from moto.moto_api import state_manager

moto/s3control/models.py

@@ -1,7 +1,6 @@
 from collections import defaultdict
 from datetime import datetime
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BackendDict, BaseModel
-from moto.core.utils import BackendDict
 from moto.moto_api._internal import mock_random
 from moto.s3.exceptions import (
     WrongPublicAccessBlockAccountIdError,

moto/sagemaker/models.py

@@ -1,8 +1,7 @@
 import json
 import os
 from datetime import datetime
-from moto.core import BaseBackend, BaseModel, CloudFormationModel
+from moto.core import BaseBackend, BackendDict, BaseModel, CloudFormationModel
-from moto.core.utils import BackendDict
 from moto.sagemaker import validators
 from moto.utilities.paginator import paginate
 from .exceptions import (