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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?
---
        operationId: 'invokeFunction'
        parameters:
            - name: 'request'
              in: body
    """
    
    arn = func_arn(function)
    
    m = re.match('(arn:aws:lambda:.*:.*:function:[a-zA-Z0-9-_]+)(:.*)?', arn)
    if m and m.group(2):
        qualifier = m.group(2)[1:]
        arn = m.group(1)
    else:
        qualifier = request.args.get('Qualifier')
    data = request.get_data()
    if data:
        data = to_str(data)
        try:
            data = json.loads(data)
        except Exception:
            try:
                
                data = json.loads(parse_chunked_data(data))
            except Exception:
                return error_response('The payload is not JSON: %s' % data, 415,
                                      error_type='UnsupportedMediaTypeException')
    
    invocation_type = request.environ.get('HTTP_X_AMZ_INVOCATION_TYPE', 'RequestResponse')
    def _create_response(result, status_code=200):