import re
from datetime import datetime, timezone, timedelta

def to_timestamp(dt_str, tz_str):
	#str转换为datetime
	dt = datetime.strptime(dt_str, '%Y-%m-%d %H:%M:%S')
	#时差正则分组
	time_diff_re = re.match('(UTC)(.\d{1,2})',tz_str)
	#取时差
	time_diff = time_diff_re.group(2)
	#设置时区
	tz_utc = timezone(timedelta(hours=int(time_diff)))
	#根据时区转化时间
	dt = dt.replace(tzinfo=tz_utc)
	#返回时间戳
	return dt.timestamp()
	
# 测试:
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('ok')