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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?
@app.route('%s/functions/<function>/configuration' % PATH_ROOT, methods=['PUT'])
def update_function_configuration(function):
    """ Update the configuration of an existing function
        ---
        operationId: 'updateFunctionConfiguration'
        parameters:
            - name: 'request'
              in: body
    """
    data = json.loads(to_str(request.data))
    arn = func_arn(function)
    
    LAMBDA_EXECUTOR.cleanup(arn)
    lambda_details = arn_to_lambda.get(arn)
    if not lambda_details:
        return error_response('Unable to find Lambda function ARN "%s"' % arn,
            404, error_type='ResourceNotFoundException')
    if data.get('Handler'):
        lambda_details.handler = data['Handler']
    if data.get('Runtime'):
        lambda_details.runtime = data['Runtime']
    lambda_details.set_dead_letter_config(data)
    env_vars = data.get('Environment', {}).get('Variables')
    if env_vars is not None:
        lambda_details.envvars = env_vars
    if data.get('Timeout'):
        lambda_details.timeout = data['Timeout']
    return jsonify(data)
@app.route('%s/functions/<function>/policy' % PATH_ROOT, methods=['POST'])
def add_permission(function):