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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?
result = []
    for m in event_source_mappings:
        if not func_name or (m['FunctionArn'] in [func_name, func_arn(func_name)]):
            if _arn_match(mapped=m['EventSourceArn'], searched=source_arn):
                result.append(m)
    return result
def _arn_match(mapped, searched):
    if not searched or mapped == searched:
        return True
    
    
    
    
    
    
    if re.match(r'^%s$' % searched, mapped):
        return True
    if mapped.startswith(searched):
        suffix = mapped[len(searched):]
        return suffix[0] == '/'
    return False
def get_function_version(arn, version):
    func = arn_to_lambda.get(arn)
    return format_func_details(func, version=version, always_add_version=True)
def publish_new_function_version(arn):
    func_details = arn_to_lambda.get(arn)
    versions = func_details.versions