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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?
sub_arn = 'arn:aws:sns:us-east-1:123456789012:test-topic:45e61c7f-dca5-4fcd-be2b-4e1b0d6eef72'
        topic_arn = 'arn:aws:sns:us-east-1:123456789012:test-topic'
        self.assertFalse(sns_listener.get_topic_by_arn(topic_arn))
        sns_listener.do_create_topic(topic_arn)
        self.assertTrue(sns_listener.get_topic_by_arn(topic_arn) is not None)
        for i in [1, 2]:
            sns_listener.do_subscribe(
                topic_arn,
                'arn:aws:sqs:us-east-1:123456789012:test-queue-1',
                'sqs',
                sub_arn,
                {}
            )
            self.assertEqual(len(sns_listener.SNS_SUBSCRIPTIONS[topic_arn]), 1)
    def test_filter_policy(self):