diff --git a/moto/managedblockchain/exceptions.py b/moto/managedblockchain/exceptions.py
index 341fe6a97..cc78adaf3 100644
--- a/moto/managedblockchain/exceptions.py
+++ b/moto/managedblockchain/exceptions.py
@@ -35,9 +35,7 @@ class BadRequestException(ManagedBlockchainClientError):
     def __init__(self, pretty_called_method, operation_error):
         super().__init__(
             "BadRequestException",
-            "An error occurred (BadRequestException) when calling the {0} operation: {1}".format(
-                pretty_called_method, operation_error
-            ),
+            f"An error occurred (BadRequestException) when calling the {pretty_called_method} operation: {operation_error}",
         )
 
 
@@ -45,9 +43,7 @@ class InvalidRequestException(ManagedBlockchainClientError):
     def __init__(self, pretty_called_method, operation_error):
         super().__init__(
             "InvalidRequestException",
-            "An error occurred (InvalidRequestException) when calling the {0} operation: {1}".format(
-                pretty_called_method, operation_error
-            ),
+            f"An error occurred (InvalidRequestException) when calling the {pretty_called_method} operation: {operation_error}",
         )
 
 
@@ -56,9 +52,7 @@ class ResourceNotFoundException(ManagedBlockchainClientError):
         self.code = 404
         super().__init__(
             "ResourceNotFoundException",
-            "An error occurred (ResourceNotFoundException) when calling the {0} operation: {1}".format(
-                pretty_called_method, operation_error
-            ),
+            f"An error occurred (ResourceNotFoundException) when calling the {pretty_called_method} operation: {operation_error}",
         )
 
 
@@ -67,9 +61,7 @@ class ResourceAlreadyExistsException(ManagedBlockchainClientError):
         self.code = 409
         super().__init__(
             "ResourceAlreadyExistsException",
-            "An error occurred (ResourceAlreadyExistsException) when calling the {0} operation: {1}".format(
-                pretty_called_method, operation_error
-            ),
+            f"An error occurred (ResourceAlreadyExistsException) when calling the {pretty_called_method} operation: {operation_error}",
         )
 
 
@@ -78,7 +70,5 @@ class ResourceLimitExceededException(ManagedBlockchainClientError):
         self.code = 429
         super().__init__(
             "ResourceLimitExceededException",
-            "An error occurred (ResourceLimitExceededException) when calling the {0} operation: {1}".format(
-                pretty_called_method, operation_error
-            ),
+            f"An error occurred (ResourceLimitExceededException) when calling the {pretty_called_method} operation: {operation_error}",
         )
diff --git a/moto/managedblockchain/models.py b/moto/managedblockchain/models.py
index 1a2ad0672..6dc5c9be4 100644
--- a/moto/managedblockchain/models.py
+++ b/moto/managedblockchain/models.py
@@ -128,15 +128,13 @@ class ManagedBlockchainNetwork(BaseModel):
         # Format for get_network
         frameworkattributes = {
             "Fabric": {
-                "OrderingServiceEndpoint": "orderer.{0}.managedblockchain.{1}.amazonaws.com:30001".format(
-                    self.id.lower(), self.region
-                ),
+                "OrderingServiceEndpoint": f"orderer.{self.id.lower()}.managedblockchain.{self.region}.amazonaws.com:30001",
                 "Edition": self.frameworkconfiguration["Fabric"]["Edition"],
             }
         }
 
-        vpcendpointname = "com.amazonaws.{0}.managedblockchain.{1}".format(
-            self.region, self.id.lower()
+        vpcendpointname = (
+            f"com.amazonaws.{self.region}.managedblockchain.{self.id.lower()}"
         )
 
         d = {
@@ -390,9 +388,7 @@ class ManagedBlockchainMember(BaseModel):
                 "AdminUsername": self.member_configuration["FrameworkConfiguration"][
                     "Fabric"
                 ]["AdminUsername"],
-                "CaEndpoint": "ca.{0}.{1}.managedblockchain.{2}.amazonaws.com:30002".format(
-                    self.id.lower(), self.networkid.lower(), self.region
-                ),
+                "CaEndpoint": f"ca.{self.id.lower()}.{self.networkid.lower()}.managedblockchain.{self.region}.amazonaws.com:30002",
             }
         }
 
@@ -464,18 +460,8 @@ class ManagedBlockchainNode(BaseModel):
         # Format for get_node
         frameworkattributes = {
             "Fabric": {
-                "PeerEndpoint": "{0}.{1}.{2}.managedblockchain.{3}.amazonaws.com:30003".format(
-                    self.id.lower(),
-                    self.networkid.lower(),
-                    self.memberid.lower(),
-                    self.region,
-                ),
-                "PeerEventEndpoint": "{0}.{1}.{2}.managedblockchain.{3}.amazonaws.com:30004".format(
-                    self.id.lower(),
-                    self.networkid.lower(),
-                    self.memberid.lower(),
-                    self.region,
-                ),
+                "PeerEndpoint": f"{self.id.lower()}.{self.networkid.lower()}.{self.memberid.lower()}.managedblockchain.{self.region}.amazonaws.com:30003",
+                "PeerEventEndpoint": f"{self.id.lower()}.{self.networkid.lower()}.{self.memberid.lower()}.managedblockchain.{self.region}.amazonaws.com:30004",
             }
         }
 
@@ -526,9 +512,7 @@ class ManagedBlockchainBackend(BaseBackend):
         if frameworkversion not in FRAMEWORKVERSIONS:
             raise BadRequestException(
                 "CreateNetwork",
-                "Invalid version {0} requested for framework HYPERLEDGER_FABRIC".format(
-                    frameworkversion
-                ),
+                f"Invalid version {frameworkversion} requested for framework HYPERLEDGER_FABRIC",
             )
 
         # Check edition
@@ -569,7 +553,7 @@ class ManagedBlockchainBackend(BaseBackend):
     def get_network(self, network_id):
         if network_id not in self.networks:
             raise ResourceNotFoundException(
-                "GetNetwork", "Network {0} not found.".format(network_id)
+                "GetNetwork", f"Network {network_id} not found."
             )
         return self.networks.get(network_id)
 
@@ -577,13 +561,13 @@ class ManagedBlockchainBackend(BaseBackend):
         # Check if network exists
         if networkid not in self.networks:
             raise ResourceNotFoundException(
-                "CreateProposal", "Network {0} not found.".format(networkid)
+                "CreateProposal", f"Network {networkid} not found."
             )
 
         # Check if member exists
         if memberid not in self.members:
             raise ResourceNotFoundException(
-                "CreateProposal", "Member {0} not found.".format(memberid)
+                "CreateProposal", f"Member {memberid} not found."
             )
 
         # CLI docs say that Invitations and Removals cannot both be passed - but it does
@@ -632,7 +616,7 @@ class ManagedBlockchainBackend(BaseBackend):
         # Check if network exists
         if networkid not in self.networks:
             raise ResourceNotFoundException(
-                "ListProposals", "Network {0} not found.".format(networkid)
+                "ListProposals", f"Network {networkid} not found."
             )
 
         proposalsfornetwork = []
@@ -647,12 +631,12 @@ class ManagedBlockchainBackend(BaseBackend):
         # Check if network exists
         if networkid not in self.networks:
             raise ResourceNotFoundException(
-                "GetProposal", "Network {0} not found.".format(networkid)
+                "GetProposal", f"Network {networkid} not found."
             )
 
         if proposalid not in self.proposals:
             raise ResourceNotFoundException(
-                "GetProposal", "Proposal {0} not found.".format(proposalid)
+                "GetProposal", f"Proposal {proposalid} not found."
             )
 
         # See if it needs to be set to expipred
@@ -663,17 +647,17 @@ class ManagedBlockchainBackend(BaseBackend):
         # Check if network exists
         if networkid not in self.networks:
             raise ResourceNotFoundException(
-                "VoteOnProposal", "Network {0} not found.".format(networkid)
+                "VoteOnProposal", f"Network {networkid} not found."
             )
 
         if proposalid not in self.proposals:
             raise ResourceNotFoundException(
-                "VoteOnProposal", "Proposal {0} not found.".format(proposalid)
+                "VoteOnProposal", f"Proposal {proposalid} not found."
             )
 
         if votermemberid not in self.members:
             raise ResourceNotFoundException(
-                "VoteOnProposal", "Member {0} not found.".format(votermemberid)
+                "VoteOnProposal", f"Member {votermemberid} not found."
             )
 
         if vote.upper() not in VOTEVALUES:
@@ -686,25 +670,21 @@ class ManagedBlockchainBackend(BaseBackend):
         if self.proposals.get(proposalid).proposal_status == "EXPIRED":
             raise InvalidRequestException(
                 "VoteOnProposal",
-                "Proposal {0} is expired and you cannot vote on it.".format(proposalid),
+                f"Proposal {proposalid} is expired and you cannot vote on it.",
             )
 
         # Check if IN_PROGRESS
         if self.proposals.get(proposalid).proposal_status != "IN_PROGRESS":
             raise InvalidRequestException(
                 "VoteOnProposal",
-                "Proposal {0} has status {1} and you cannot vote on it.".format(
-                    proposalid, self.proposals.get(proposalid).proposal_status
-                ),
+                f"Proposal {proposalid} has status {self.proposals.get(proposalid).proposal_status} and you cannot vote on it.",
             )
 
         # Check to see if this member already voted
         if votermemberid in self.proposals.get(proposalid).proposal_votes:
             raise ResourceAlreadyExistsException(
                 "VoteOnProposal",
-                "Member {0} has already voted on proposal {1}.".format(
-                    votermemberid, proposalid
-                ),
+                f"Member {votermemberid} has already voted on proposal {proposalid}.",
             )
 
         # Cast vote
@@ -741,12 +721,12 @@ class ManagedBlockchainBackend(BaseBackend):
         # Check if network exists
         if networkid not in self.networks:
             raise ResourceNotFoundException(
-                "ListProposalVotes", "Network {0} not found.".format(networkid)
+                "ListProposalVotes", f"Network {networkid} not found."
             )
 
         if proposalid not in self.proposals:
             raise ResourceNotFoundException(
-                "ListProposalVotes", "Proposal {0} not found.".format(proposalid)
+                "ListProposalVotes", f"Proposal {proposalid} not found."
             )
 
         # Output the vote summaries
@@ -765,7 +745,7 @@ class ManagedBlockchainBackend(BaseBackend):
     def reject_invitation(self, invitationid):
         if invitationid not in self.invitations:
             raise ResourceNotFoundException(
-                "RejectInvitation", "InvitationId {0} not found.".format(invitationid)
+                "RejectInvitation", f"InvitationId {invitationid} not found."
             )
         self.invitations.get(invitationid).reject_invitation()
 
@@ -773,30 +753,25 @@ class ManagedBlockchainBackend(BaseBackend):
         # Check if network exists
         if networkid not in self.networks:
             raise ResourceNotFoundException(
-                "CreateMember", "Network {0} not found.".format(networkid)
+                "CreateMember", f"Network {networkid} not found."
             )
 
         if invitationid not in self.invitations:
             raise InvalidRequestException(
-                "CreateMember", "Invitation {0} not valid".format(invitationid)
+                "CreateMember", f"Invitation {invitationid} not valid"
             )
 
         if self.invitations.get(invitationid).invitation_status != "PENDING":
             raise InvalidRequestException(
-                "CreateMember", "Invitation {0} not valid".format(invitationid)
+                "CreateMember", f"Invitation {invitationid} not valid"
             )
 
-        if (
-            member_name_exist_in_network(
-                self.members, networkid, member_configuration["Name"]
-            )
-            is True
+        if member_name_exist_in_network(
+            self.members, networkid, member_configuration["Name"]
         ):
             raise InvalidRequestException(
                 "CreateMember",
-                "Member name {0} already exists in network {1}.".format(
-                    member_configuration["Name"], networkid
-                ),
+                f"Member name {member_configuration['Name']} already exists in network {networkid}.",
             )
 
         networkedition = self.networks.get(networkid).network_edition
@@ -806,9 +781,7 @@ class ManagedBlockchainBackend(BaseBackend):
         ):
             raise ResourceLimitExceededException(
                 "CreateMember",
-                "You cannot create a member in network {0}.{1} is the maximum number of members allowed in a {2} Edition network.".format(
-                    networkid, EDITIONS[networkedition]["MaxMembers"], networkedition
-                ),
+                f"You cannot create a member in network {networkid}.{EDITIONS[networkedition]['MaxMembers']} is the maximum number of members allowed in a {networkedition} Edition network.",
             )
 
         memberadminpassword = member_configuration["FrameworkConfiguration"]["Fabric"][
@@ -836,7 +809,7 @@ class ManagedBlockchainBackend(BaseBackend):
         # Check if network exists
         if networkid not in self.networks:
             raise ResourceNotFoundException(
-                "ListMembers", "Network {0} not found.".format(networkid)
+                "ListMembers", f"Network {networkid} not found."
             )
 
         membersfornetwork = []
@@ -849,18 +822,18 @@ class ManagedBlockchainBackend(BaseBackend):
         # Check if network exists
         if networkid not in self.networks:
             raise ResourceNotFoundException(
-                "GetMember", "Network {0} not found.".format(networkid)
+                "GetMember", f"Network {networkid} not found."
             )
 
         if memberid not in self.members:
             raise ResourceNotFoundException(
-                "GetMember", "Member {0} not found.".format(memberid)
+                "GetMember", f"Member {memberid} not found."
             )
 
         # Cannot get a member than has been deleted (it does show up in the list)
         if self.members.get(memberid).member_status == "DELETED":
             raise ResourceNotFoundException(
-                "GetMember", "Member {0} not found.".format(memberid)
+                "GetMember", f"Member {memberid} not found."
             )
 
         return self.members.get(memberid)
@@ -869,12 +842,12 @@ class ManagedBlockchainBackend(BaseBackend):
         # Check if network exists
         if networkid not in self.networks:
             raise ResourceNotFoundException(
-                "DeleteMember", "Network {0} not found.".format(networkid)
+                "DeleteMember", f"Network {networkid} not found."
             )
 
         if memberid not in self.members:
             raise ResourceNotFoundException(
-                "DeleteMember", "Member {0} not found.".format(memberid)
+                "DeleteMember", f"Member {memberid} not found."
             )
 
         self.members.get(memberid).delete()
@@ -902,12 +875,12 @@ class ManagedBlockchainBackend(BaseBackend):
         # Check if network exists
         if networkid not in self.networks:
             raise ResourceNotFoundException(
-                "UpdateMember", "Network {0} not found.".format(networkid)
+                "UpdateMember", f"Network {networkid} not found."
             )
 
         if memberid not in self.members:
             raise ResourceNotFoundException(
-                "UpdateMember", "Member {0} not found.".format(memberid)
+                "UpdateMember", f"Member {memberid} not found."
             )
 
         self.members.get(memberid).update(logpublishingconfiguration)
@@ -923,12 +896,12 @@ class ManagedBlockchainBackend(BaseBackend):
         # Check if network exists
         if networkid not in self.networks:
             raise ResourceNotFoundException(
-                "CreateNode", "Network {0} not found.".format(networkid)
+                "CreateNode", f"Network {networkid} not found."
             )
 
         if memberid not in self.members:
             raise ResourceNotFoundException(
-                "CreateNode", "Member {0} not found.".format(memberid)
+                "CreateNode", f"Member {memberid} not found."
             )
 
         networkedition = self.networks.get(networkid).network_edition
@@ -938,11 +911,7 @@ class ManagedBlockchainBackend(BaseBackend):
         ):
             raise ResourceLimitExceededException(
                 "CreateNode",
-                "Maximum number of nodes exceeded in member {0}. The maximum number of nodes you can have in a member in a {1} Edition network is {2}".format(
-                    memberid,
-                    networkedition,
-                    EDITIONS[networkedition]["MaxNodesPerMember"],
-                ),
+                f"Maximum number of nodes exceeded in member {memberid}. The maximum number of nodes you can have in a member in a {networkedition} Edition network is {EDITIONS[networkedition]['MaxNodesPerMember']}",
             )
 
         # See if the instance family is correct
@@ -956,7 +925,7 @@ class ManagedBlockchainBackend(BaseBackend):
         if correctinstancefamily is False:
             raise InvalidRequestException(
                 "CreateNode",
-                "Requested instance {0} isn't supported.".format(instancetype),
+                f"Requested instance {instancetype} isn't supported.",
             )
 
         # Check for specific types for starter
@@ -964,9 +933,7 @@ class ManagedBlockchainBackend(BaseBackend):
             if instancetype not in EDITIONS["STARTER"]["AllowedNodeInstanceTypes"]:
                 raise InvalidRequestException(
                     "CreateNode",
-                    "Instance type {0} is not supported with STARTER Edition networks.".format(
-                        instancetype
-                    ),
+                    f"Instance type {instancetype} is not supported with STARTER Edition networks.",
                 )
 
         # Simple availability zone check
@@ -994,18 +961,18 @@ class ManagedBlockchainBackend(BaseBackend):
     def list_nodes(self, networkid, memberid, status=None):
         if networkid not in self.networks:
             raise ResourceNotFoundException(
-                "ListNodes", "Network {0} not found.".format(networkid)
+                "ListNodes", f"Network {networkid} not found."
             )
 
         if memberid not in self.members:
             raise ResourceNotFoundException(
-                "ListNodes", "Member {0} not found.".format(memberid)
+                "ListNodes", f"Member {memberid} not found."
             )
 
         # If member is deleted, cannot list nodes
         if self.members.get(memberid).member_status == "DELETED":
             raise ResourceNotFoundException(
-                "ListNodes", "Member {0} not found.".format(memberid)
+                "ListNodes", f"Member {memberid} not found."
             )
 
         nodesformember = []
@@ -1020,24 +987,18 @@ class ManagedBlockchainBackend(BaseBackend):
         # Check if network exists
         if networkid not in self.networks:
             raise ResourceNotFoundException(
-                "GetNode", "Network {0} not found.".format(networkid)
+                "GetNode", f"Network {networkid} not found."
             )
 
         if memberid not in self.members:
-            raise ResourceNotFoundException(
-                "GetNode", "Member {0} not found.".format(memberid)
-            )
+            raise ResourceNotFoundException("GetNode", f"Member {memberid} not found.")
 
         if nodeid not in self.nodes:
-            raise ResourceNotFoundException(
-                "GetNode", "Node {0} not found.".format(nodeid)
-            )
+            raise ResourceNotFoundException("GetNode", f"Node {nodeid} not found.")
 
         # Cannot get a node than has been deleted (it does show up in the list)
         if self.nodes.get(nodeid).node_status == "DELETED":
-            raise ResourceNotFoundException(
-                "GetNode", "Node {0} not found.".format(nodeid)
-            )
+            raise ResourceNotFoundException("GetNode", f"Node {nodeid} not found.")
 
         return self.nodes.get(nodeid)
 
@@ -1045,18 +1006,16 @@ class ManagedBlockchainBackend(BaseBackend):
         # Check if network exists
         if networkid not in self.networks:
             raise ResourceNotFoundException(
-                "DeleteNode", "Network {0} not found.".format(networkid)
+                "DeleteNode", f"Network {networkid} not found."
             )
 
         if memberid not in self.members:
             raise ResourceNotFoundException(
-                "DeleteNode", "Member {0} not found.".format(memberid)
+                "DeleteNode", f"Member {memberid} not found."
             )
 
         if nodeid not in self.nodes:
-            raise ResourceNotFoundException(
-                "DeleteNode", "Node {0} not found.".format(nodeid)
-            )
+            raise ResourceNotFoundException("DeleteNode", f"Node {nodeid} not found.")
 
         self.nodes.get(nodeid).delete()
 
@@ -1064,18 +1023,16 @@ class ManagedBlockchainBackend(BaseBackend):
         # Check if network exists
         if networkid not in self.networks:
             raise ResourceNotFoundException(
-                "UpdateNode", "Network {0} not found.".format(networkid)
+                "UpdateNode", f"Network {networkid} not found."
             )
 
         if memberid not in self.members:
             raise ResourceNotFoundException(
-                "UpdateNode", "Member {0} not found.".format(memberid)
+                "UpdateNode", f"Member {memberid} not found."
             )
 
         if nodeid not in self.nodes:
-            raise ResourceNotFoundException(
-                "UpdateNode", "Node {0} not found.".format(nodeid)
-            )
+            raise ResourceNotFoundException("UpdateNode", f"Node {nodeid} not found.")
 
         self.nodes.get(nodeid).update(logpublishingconfiguration)
 
diff --git a/moto/mediaconnect/models.py b/moto/mediaconnect/models.py
index 2aa945cbc..3d0f90729 100644
--- a/moto/mediaconnect/models.py
+++ b/moto/mediaconnect/models.py
@@ -215,9 +215,7 @@ class MediaConnectBackend(BaseBackend):
             flow = self._flows[flow_arn]
             flow.vpc_interfaces = vpc_interfaces
         else:
-            raise NotFoundException(
-                message="flow with arn={} not found".format(flow_arn)
-            )
+            raise NotFoundException(message=f"flow with arn={flow_arn} not found")
         return flow_arn, flow.vpc_interfaces
 
     def add_flow_outputs(self, flow_arn, outputs):
@@ -225,9 +223,7 @@ class MediaConnectBackend(BaseBackend):
             flow = self._flows[flow_arn]
             flow.outputs = outputs
         else:
-            raise NotFoundException(
-                message="flow with arn={} not found".format(flow_arn)
-            )
+            raise NotFoundException(message=f"flow with arn={flow_arn} not found")
         return flow_arn, flow.outputs
 
     def remove_flow_vpc_interface(self, flow_arn, vpc_interface_name):
@@ -239,9 +235,7 @@ class MediaConnectBackend(BaseBackend):
                 if vpc_interface["name"] != vpc_interface_name
             ]
         else:
-            raise NotFoundException(
-                message="flow with arn={} not found".format(flow_arn)
-            )
+            raise NotFoundException(message=f"flow with arn={flow_arn} not found")
         return flow_arn, vpc_interface_name
 
     def remove_flow_output(self, flow_arn, output_name):
@@ -253,9 +247,7 @@ class MediaConnectBackend(BaseBackend):
                 if output["name"] != output_name
             ]
         else:
-            raise NotFoundException(
-                message="flow with arn={} not found".format(flow_arn)
-            )
+            raise NotFoundException(message=f"flow with arn={flow_arn} not found")
         return flow_arn, output_name
 
     def update_flow_output(
@@ -279,9 +271,7 @@ class MediaConnectBackend(BaseBackend):
         vpc_interface_attachment,
     ):
         if flow_arn not in self._flows:
-            raise NotFoundException(
-                message="flow with arn={} not found".format(flow_arn)
-            )
+            raise NotFoundException(message=f"flow with arn={flow_arn} not found")
         flow = self._flows[flow_arn]
         for output in flow.outputs:
             if output["outputArn"] == output_arn:
@@ -303,15 +293,11 @@ class MediaConnectBackend(BaseBackend):
                 output["streamId"] = stream_id
                 output["vpcInterfaceAttachment"] = vpc_interface_attachment
                 return flow_arn, output
-        raise NotFoundException(
-            message="output with arn={} not found".format(output_arn)
-        )
+        raise NotFoundException(message=f"output with arn={output_arn} not found")
 
     def add_flow_sources(self, flow_arn, sources):
         if flow_arn not in self._flows:
-            raise NotFoundException(
-                message="flow with arn={} not found".format(flow_arn)
-            )
+            raise NotFoundException(message=f"flow with arn={flow_arn} not found")
         flow = self._flows[flow_arn]
         for source in sources:
             source_id = random.uuid4().hex
@@ -342,9 +328,7 @@ class MediaConnectBackend(BaseBackend):
         whitelist_cidr,
     ):
         if flow_arn not in self._flows:
-            raise NotFoundException(
-                message="flow with arn={} not found".format(flow_arn)
-            )
+            raise NotFoundException(message=f"flow with arn={flow_arn} not found")
         flow = self._flows[flow_arn]
         source = next(
             iter(
@@ -378,9 +362,7 @@ class MediaConnectBackend(BaseBackend):
         entitlements,
     ):
         if flow_arn not in self._flows:
-            raise NotFoundException(
-                message="flow with arn={} not found".format(flow_arn)
-            )
+            raise NotFoundException(message=f"flow with arn={flow_arn} not found")
         flow = self._flows[flow_arn]
         for entitlement in entitlements:
             entitlement_id = random.uuid4().hex
@@ -393,16 +375,14 @@ class MediaConnectBackend(BaseBackend):
 
     def revoke_flow_entitlement(self, flow_arn, entitlement_arn):
         if flow_arn not in self._flows:
-            raise NotFoundException(
-                message="flow with arn={} not found".format(flow_arn)
-            )
+            raise NotFoundException(message=f"flow with arn={flow_arn} not found")
         flow = self._flows[flow_arn]
         for entitlement in flow.entitlements:
             if entitlement_arn == entitlement["entitlementArn"]:
                 flow.entitlements.remove(entitlement)
                 return flow_arn, entitlement_arn
         raise NotFoundException(
-            message="entitlement with arn={} not found".format(entitlement_arn)
+            message=f"entitlement with arn={entitlement_arn} not found"
         )
 
     def update_flow_entitlement(
@@ -416,9 +396,7 @@ class MediaConnectBackend(BaseBackend):
         subscribers,
     ):
         if flow_arn not in self._flows:
-            raise NotFoundException(
-                message="flow with arn={} not found".format(flow_arn)
-            )
+            raise NotFoundException(message=f"flow with arn={flow_arn} not found")
         flow = self._flows[flow_arn]
         for entitlement in flow.entitlements:
             if entitlement_arn == entitlement["entitlementArn"]:
@@ -429,7 +407,7 @@ class MediaConnectBackend(BaseBackend):
                 entitlement["subscribers"] = subscribers
                 return flow_arn, entitlement
         raise NotFoundException(
-            message="entitlement with arn={} not found".format(entitlement_arn)
+            message=f"entitlement with arn={entitlement_arn} not found"
         )
 
         # add methods from here
diff --git a/moto/medialive/models.py b/moto/medialive/models.py
index 46e8e50f4..3213b967c 100644
--- a/moto/medialive/models.py
+++ b/moto/medialive/models.py
@@ -134,7 +134,7 @@ class MediaLiveBackend(BaseBackend):
         The RequestID and Reserved parameters are not yet implemented
         """
         channel_id = mock_random.uuid4().hex
-        arn = "arn:aws:medialive:channel:{}".format(channel_id)
+        arn = f"arn:aws:medialive:channel:{channel_id}"
         channel = Channel(
             arn=arn,
             cdi_input_specification=cdi_input_specification,
@@ -228,7 +228,7 @@ class MediaLiveBackend(BaseBackend):
         The VPC and RequestId parameters are not yet implemented
         """
         input_id = mock_random.uuid4().hex
-        arn = "arn:aws:medialive:input:{}".format(input_id)
+        arn = f"arn:aws:medialive:input:{input_id}"
         a_input = Input(
             arn=arn,
             input_id=input_id,
diff --git a/moto/mediapackage/models.py b/moto/mediapackage/models.py
index c8bd3701c..22a1bc66a 100644
--- a/moto/mediapackage/models.py
+++ b/moto/mediapackage/models.py
@@ -73,7 +73,7 @@ class MediaPackageBackend(BaseBackend):
         self._origin_endpoints = OrderedDict()
 
     def create_channel(self, description, channel_id, tags):
-        arn = "arn:aws:mediapackage:channel:{}".format(channel_id)
+        arn = f"arn:aws:mediapackage:channel:{channel_id}"
         channel = Channel(
             arn=arn,
             description=description,
@@ -97,7 +97,7 @@ class MediaPackageBackend(BaseBackend):
             return channel.to_dict()
         except KeyError:
             error = "NotFoundException"
-            raise ClientError(error, "channel with id={} not found".format(channel_id))
+            raise ClientError(error, f"channel with id={channel_id} not found")
 
     def delete_channel(self, channel_id):
         try:
@@ -107,7 +107,7 @@ class MediaPackageBackend(BaseBackend):
 
         except KeyError:
             error = "NotFoundException"
-            raise ClientError(error, "channel with id={} not found".format(channel_id))
+            raise ClientError(error, f"channel with id={channel_id} not found")
 
     def create_origin_endpoint(
         self,
@@ -126,10 +126,8 @@ class MediaPackageBackend(BaseBackend):
         time_delay_seconds,
         whitelist,
     ):
-        arn = "arn:aws:mediapackage:origin_endpoint:{}".format(endpoint_id)
-        url = "https://origin-endpoint.mediapackage.{}.amazonaws.com/{}".format(
-            self.region_name, endpoint_id
-        )
+        arn = f"arn:aws:mediapackage:origin_endpoint:{endpoint_id}"
+        url = f"https://origin-endpoint.mediapackage.{self.region_name}.amazonaws.com/{endpoint_id}"
         origin_endpoint = OriginEndpoint(
             arn=arn,
             authorization=authorization,
@@ -157,9 +155,7 @@ class MediaPackageBackend(BaseBackend):
             return origin_endpoint.to_dict()
         except KeyError:
             error = "NotFoundException"
-            raise ClientError(
-                error, "origin endpoint with id={} not found".format(endpoint_id)
-            )
+            raise ClientError(error, f"origin endpoint with id={endpoint_id} not found")
 
     def list_origin_endpoints(self):
         origin_endpoints = list(self._origin_endpoints.values())
@@ -173,9 +169,7 @@ class MediaPackageBackend(BaseBackend):
             return origin_endpoint.to_dict()
         except KeyError:
             error = "NotFoundException"
-            raise ClientError(
-                error, "origin endpoint with id={} not found".format(endpoint_id)
-            )
+            raise ClientError(error, f"origin endpoint with id={endpoint_id} not found")
 
     def update_origin_endpoint(
         self,
@@ -209,9 +203,7 @@ class MediaPackageBackend(BaseBackend):
 
         except KeyError:
             error = "NotFoundException"
-        raise ClientError(
-            error, "origin endpoint with id={} not found".format(endpoint_id)
-        )
+        raise ClientError(error, f"origin endpoint with id={endpoint_id} not found")
 
 
 mediapackage_backends = BackendDict(MediaPackageBackend, "mediapackage")
diff --git a/moto/mediastore/models.py b/moto/mediastore/models.py
index 5ca579c12..5ef8c7b28 100644
--- a/moto/mediastore/models.py
+++ b/moto/mediastore/models.py
@@ -42,11 +42,11 @@ class MediaStoreBackend(BaseBackend):
         self._containers = OrderedDict()
 
     def create_container(self, name, tags):
-        arn = "arn:aws:mediastore:container:{}".format(name)
+        arn = f"arn:aws:mediastore:container:{name}"
         container = Container(
             arn=arn,
             name=name,
-            endpoint="/{}".format(name),
+            endpoint=f"/{name}",
             status="CREATING",
             creation_time=date.today().strftime("%m/%d/%Y, %H:%M:%S"),
             tags=tags,
diff --git a/moto/mediastoredata/models.py b/moto/mediastoredata/models.py
index 0f964674b..7185ea9d2 100644
--- a/moto/mediastoredata/models.py
+++ b/moto/mediastoredata/models.py
@@ -45,7 +45,7 @@ class MediaStoreDataBackend(BaseBackend):
     def delete_object(self, path):
         if path not in self._objects:
             error = "ObjectNotFoundException"
-            raise ClientError(error, "Object with id={} not found".format(path))
+            raise ClientError(error, f"Object with id={path} not found")
         del self._objects[path]
         return {}
 
@@ -56,7 +56,7 @@ class MediaStoreDataBackend(BaseBackend):
         objects_found = [item for item in self._objects.values() if item.path == path]
         if len(objects_found) == 0:
             error = "ObjectNotFoundException"
-            raise ClientError(error, "Object with id={} not found".format(path))
+            raise ClientError(error, f"Object with id={path} not found")
         return objects_found[0]
 
     def list_items(self):
diff --git a/moto/moto_server/utilities.py b/moto/moto_server/utilities.py
index bf8e504e9..3753b502b 100644
--- a/moto/moto_server/utilities.py
+++ b/moto/moto_server/utilities.py
@@ -23,10 +23,8 @@ class AWSTestHelper(FlaskClient):
         opts = {"Action": action_name}
         opts.update(kwargs)
         res = self.get(
-            "/?{0}".format(urlencode(opts)),
-            headers={
-                "Host": "{0}.us-east-1.amazonaws.com".format(self.application.service)
-            },
+            f"/?{urlencode(opts)}",
+            headers={"Host": f"{self.application.service}.us-east-1.amazonaws.com"},
         )
         return res.data.decode("utf-8")
 
diff --git a/moto/moto_server/werkzeug_app.py b/moto/moto_server/werkzeug_app.py
index fc98a046c..ab07f3bc7 100644
--- a/moto/moto_server/werkzeug_app.py
+++ b/moto/moto_server/werkzeug_app.py
@@ -74,15 +74,13 @@ class DomainDispatcherApplication(object):
             return host
 
         for backend, pattern in self.backend_url_patterns:
-            if pattern.match("http://%s" % host):
+            if pattern.match(f"http://{host}"):
                 return backend
 
         if "amazonaws.com" in host:
             print(  # noqa
-                "Unable to find appropriate backend for {}."
-                "Remember to add the URL to urls.py, and run scripts/update_backend_index.py to index it.".format(
-                    host
-                )
+                f"Unable to find appropriate backend for {host}."
+                "Remember to add the URL to urls.py, and run scripts/update_backend_index.py to index it."
             )
 
     def infer_service_region_host(self, body, environ):
@@ -129,9 +127,7 @@ class DomainDispatcherApplication(object):
         elif service == "mediastore" and not target:
             # All MediaStore API calls have a target header
             # If no target is set, assume we're trying to reach the mediastore-data service
-            host = "data.{service}.{region}.amazonaws.com".format(
-                service=service, region=region
-            )
+            host = f"data.{service}.{region}.amazonaws.com"
         elif service == "dynamodb":
             if environ["HTTP_X_AMZ_TARGET"].startswith("DynamoDBStreams"):
                 host = "dynamodbstreams"
@@ -145,21 +141,15 @@ class DomainDispatcherApplication(object):
                 else:
                     host = "dynamodb"
         elif service == "sagemaker":
-            host = "api.{service}.{region}.amazonaws.com".format(
-                service=service, region=region
-            )
+            host = f"api.{service}.{region}.amazonaws.com"
         elif service == "timestream":
-            host = "ingest.{service}.{region}.amazonaws.com".format(
-                service=service, region=region
-            )
+            host = f"ingest.{service}.{region}.amazonaws.com"
         elif service == "s3" and (
             path.startswith("/v20180820/") or "s3-control" in environ["HTTP_HOST"]
         ):
             host = "s3control"
         else:
-            host = "{service}.{region}.amazonaws.com".format(
-                service=service, region=region
-            )
+            host = f"{service}.{region}.amazonaws.com"
 
         return host
 
@@ -281,7 +271,7 @@ def create_backend_app(service):
     for url_path, handler in backend.flask_paths.items():
         view_func = convert_to_flask_response(handler)
         if handler.__name__ == "dispatch":
-            endpoint = "{0}.dispatch".format(handler.__self__.__name__)
+            endpoint = f"{handler.__self__.__name__}.dispatch"
         else:
             endpoint = view_func.__name__