def iso_format(datetime):
    """
    Generates an ISO formatted datetime based on what the LaunchKey API expects.
    This is a standard ISO datetime without microseconds.
    :param datetime: datetime.datetime object
    :return: ISO formatted string IE: 2017-10-03T22:50:15Z
    """
    return datetime.strftime("%Y-%m-%dT%H:%M:%SZ") if datetime is not None else None