Merge pull request #2564 from bblommers/bugfix/2562

#2562 - DynamoDB - allow updates to be of a different type

moto/dynamodb2/models.py

@@ -77,6 +77,7 @@ class DynamoType(object):
             attr, list_index = attribute_is_list(attr)
             if not key:
                 # {'S': value} ==> {'S': new_value}
+                self.type = new_value.type
                 self.value = new_value.value
             else:
                 if attr not in self.value:  # nonexistingattribute