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Under utils/common.py, 

TIMESTAMP_FORMAT_MILLIS = '%Y-%m-%dT%H:%M:%S.%fZ'

The %f produces time with microseconds, for example: 2020-03-18T19:43:18.115783Z.


However, when interacting the AWS s3 and sns apis, I receive DateTimes like this:

2020-03-02T22:32:13.240Z
i.e. milliseconds. 

This seems like a simple change to the utils. TIMESTAMP_FORMAT_MILLIS is named as if it should be millis as well. This is seems like a simple change. Is there a reason it should be microseconds?
action = {
            'Message': ['{"default": {"message": "abc"}}'],
            'MessageStructure': ['json']
        }
        result_str = sns_listener.create_sns_message_body(self.subscriber, action)
        result = json.loads(result_str)
        self.assertEqual(result['Message'], {'message': 'abc'})
    def test_create_sns_message_body_json_structure_without_default_key(self):
        action = {
            'Message': ['{"message": "abc"}'],
            'MessageStructure': ['json']
        }
        with self.assertRaises(Exception) as exc:
            sns_listener.create_sns_message_body(self.subscriber, action)
        self.assertEqual(str(exc.exception), "Unable to find 'default' key in message payload")
    def test_create_sns_message_body_json_structure_sqs_protocol(self):
        action = {
            'Message': ['{"default": "default message", "sqs": "sqs message"}'],
            'MessageStructure': ['json']
        }
        result_str = sns_listener.create_sns_message_body(self.subscriber, action)
        result = json.loads(result_str)
        self.assertEqual(result['Message'], 'sqs message')
    def test_create_sqs_message_attributes(self):