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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?
""" Get an existing event source mapping
        ---
        operationId: 'getEventSourceMapping'
        parameters:
            - name: 'request'
              in: body
    """
    mappings = event_source_mappings
    mappings = [m for m in mappings if mapping_uuid == m.get('UUID')]
    if len(mappings) == 0:
        return not_found_error()
    return jsonify(mappings[0])
@app.route('%s/event-source-mappings/' % PATH_ROOT, methods=['POST'])
def create_event_source_mapping():
    """ Create new event source mapping
        ---
        operationId: 'createEventSourceMapping'
        parameters:
            - name: 'request'
              in: body
    """
    data = json.loads(to_str(request.data))
    mapping = add_event_source(
        data['FunctionName'], data['EventSourceArn'], data.get('Enabled'), data.get('BatchSize')
    )
    return jsonify(mapping)
@app.route('%s/event-source-mappings/<mapping_uuid>' % PATH_ROOT, methods=['PUT'])
def update_event_source_mapping(mapping_uuid):