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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?
""" Update an existing event source mapping
        ---
        operationId: 'updateEventSourceMapping'
        parameters:
            - name: 'request'
              in: body
    """
    data = json.loads(request.data)
    if not mapping_uuid:
        return jsonify({})
    function_name = data.get('FunctionName') or ''
    enabled = data.get('Enabled', True)
    batch_size = data.get('BatchSize') or 100
    mapping = update_event_source(mapping_uuid, function_name, enabled, batch_size)
    return jsonify(mapping)
@app.route('%s/event-source-mappings/<mapping_uuid>' % PATH_ROOT, methods=['DELETE'])
def delete_event_source_mapping(mapping_uuid):