From 0a7d299da3594ca90082c2389c39dd3e750a57a8 Mon Sep 17 00:00:00 2001
From: Asher Foa <1268088+asherf@users.noreply.github.com>
Date: Fri, 20 Dec 2019 11:18:04 -0800
Subject: [PATCH] Fix json encoding issue.

---
 moto/dynamodb2/models.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/moto/dynamodb2/models.py b/moto/dynamodb2/models.py
index 121f564a4..784dfc5d7 100644
--- a/moto/dynamodb2/models.py
+++ b/moto/dynamodb2/models.py
@@ -586,7 +586,7 @@ class StreamRecord(BaseModel):
             self.record["dynamodb"]["OldImage"] = old_a
 
         # This is a substantial overestimate but it's the easiest to do now
-        self.record["dynamodb"]["SizeBytes"] = len(json.dumps(self.record["dynamodb"]))
+        self.record["dynamodb"]["SizeBytes"] = len(dynamo_json_dump(self.record["dynamodb"]))
 
     def to_json(self):
         return self.record