# -*- coding:utf-8 -*-
import re
from datetime import datetime, timezone, timedelta

def to_timestamp(dt_str, tz_str):
    dt=datetime.strptime(dt_str,'%Y-%m-%d %H:%M:%S')
    n=re.match(r'UTC([+|-]\d+):00',tz_str).group(1)
    n=int(n)
    utc_dt=dt.replace(tzinfo=timezone(timedelta(hours=n)))
    return utc_dt.timestamp()

t1 = to_timestamp('2015-6-1 08:10:30', 'UTC+7:00')
assert t1 == 1433121030.0, t1

t2 = to_timestamp('2015-5-31 16:10:30', 'UTC-09:00')
assert t2 == 1433121030.0, t2

print('Pass')