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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?
for i, m in enumerate(event_source_mappings):
        if uuid_value == m['UUID']:
            return event_source_mappings.pop(i)
    return {}
def use_docker():
    global DO_USE_DOCKER
    if DO_USE_DOCKER is None:
        DO_USE_DOCKER = False
        if 'docker' in config.LAMBDA_EXECUTOR:
            try:
                run('docker images', print_error=False)
                DO_USE_DOCKER = True
            except Exception:
                pass
    return DO_USE_DOCKER
def process_apigateway_invocation(func_arn, path, payload, headers={},
        resource_path=None, method=None, path_params={},
        query_string_params={}, request_context={}):
    try:
        resource_path = resource_path or path
        event = {
            'path': path,
            'headers': dict(headers),
            'pathParameters': dict(path_params),