def to_timestamp(dt_str, tz_str):
    hours = re.match(r'UTC([\+\-]?\d{0,2}):\d*',tz_str).group(1)
    d = datetime.strptime(dt_str,'%Y-%m-%d %H:%M:%S')
    tz_utc = timezone(timedelta(hours=int(hours)))
    d = d.replace(tzinfo=tz_utc)
    return d.timestamp()