def unixtimestamp(datetime):
    """Get unix time stamp from that given datetime. If datetime
    is not tzaware then it's assumed that it is UTC
    """
    epoch = UTC.localize(datetime.utcfromtimestamp(0))
    if not datetime.tzinfo:
        dt = UTC.localize(datetime)
    else:
        dt = UTC.normalize(datetime)
    delta = dt - epoch
    return total_seconds(delta)
Get unix time stamp from that given datetime. If datetime
    is not tzaware then it's assumed that it is UTC