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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?
req_data = {
            'Attribute.entry.1.key': ['RawMessageDelivery'],
            'Attribute.entry.1.value': ['true'],
            'Attribute.entry.2.key': ['FilterPolicy'],
            'Attribute.entry.2.value': ['{"type": ["foo", "bar"]}']
        }
        attributes = sns_listener.get_subscribe_attributes(req_data)
        self.assertDictEqual(
            attributes,
            {
                'RawMessageDelivery': 'true',
                'FilterPolicy': '{"type": ["foo", "bar"]}'
            }
        )
    def test_create_sns_message_body_raw_message_delivery(self):