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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?
regex = r'^(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=)?$'
    return is_string(s) and re.match(regex, s)
def md5(string):
    m = hashlib.md5()
    m.update(to_bytes(string))
    return m.hexdigest()
def in_docker():
    return config.in_docker()
def has_docker():
    try:
        run('docker ps')
        return True
    except Exception:
        return False
def get_docker_container_names():
    return bootstrap.get_docker_container_names()
def is_port_open(port_or_url, http_path=None, expect_success=True, protocols=['tcp']):
    port = port_or_url
    host = 'localhost'
    protocol = 'http'
    protocols = protocols if isinstance(protocols, list) else [protocols]
    if isinstance(port, six.string_types):
        url = urlparse(port_or_url)
        port = url.port
        host = url.hostname
        protocol = url.scheme
    nw_protocols = []
    nw_protocols += ([socket.SOCK_STREAM] if 'tcp' in protocols else [])
    nw_protocols += ([socket.SOCK_DGRAM] if 'udp' in protocols else [])
    for nw_protocol in nw_protocols: