PST 时间比较特殊，存在夏令时和冬令时，夏令时，又称 “日光节约时制”（Daylight Saving Time），是一种为节约能源而人为规定地方时间的制度，在这一制度实行期间所采用的统一时间称为 “夏令时”。一般在天亮早的夏季人为将时间提前一小时（或者说将时钟拨快 1 个小时，以美国为例，美国的标准时区是西八区，标准时间应是 GMT-8，但由于此时是夏令时，美国时间就是 GMT-7），可以使人早起早睡，减少照明量，以充分利用光照资源，从而节约照明用电。各个采纳夏时制的国家具体规定不同。全世界有近 110 个国家每年要实行夏令时。而冬令时会将时钟调整为原来标准时间（即时钟重新拨回 1 小时，此时美国时间就是标准的 GMT-8）
from datetime import datetime
from pytz import utc, timezone
def get_current_pst_time():
"""
获取当前时间的太平洋时间（可能是夏令时，也可能是冬令时）
"""
print('------------(1) Current time to PST time----------------')
local_time = datetime.now().strftime('%Y-%m-%d %H:%M:%S')
utc_time = datetime.now(tz=utc).strftime('%Y-%m-%d %H:%M:%S')
pst_time = datetime.now(tz=utc).astimezone(timezone('US/Pacific')).strftime('%Y-%m-%d %H:%M:%S')
is_summary_time = bool(datetime.now(tz=utc).astimezone(timezone('US/Pacific')).dst())
print('is it a summary time? %s.' % is_summary_time)
print('local time is %s.' % local_time)
print('utc time is %s.' % utc_time)
print('pst time is %s.' % pst_time)
def convert_pst_time_to_utc_time(pst_time_str):
print('------------(2) PST time to UTC time----------------')
print('pst time is %s.' % pst_time_str)
temp_time = datetime.strptime(pst_time_str, '%Y-%m-%d %H:%M:%S')
pacific_timezone = timezone('US/Pacific')
pst_time = pacific_timezone.localize(temp_time, is_dst=None)
assert pst_time.tzinfo is not None
assert pst_time.tzinfo.utcoffset(pst_time) is not None
is_summary_time = bool(pst_time.dst())
print('is it a summary time? %s.' % is_summary_time)
utc_time = pst_time.astimezone(timezone('utc'))
print('utc time is %s.' % utc_time.strftime('%Y-%m-%d %H:%M:%S'))
def convert_utc_time_to_pst_time(utc_time_str):
print('------------(3) UTC time to PST time----------------')
print('utc time is %s.' % utc_time_str)
temp_time = datetime.strptime(utc_time_str, '%Y-%m-%d %H:%M:%S')
utc_timezone = timezone('utc')
utc_time = utc_timezone.localize(temp_time, is_dst=None)
assert utc_time.tzinfo is not None
assert utc_time.tzinfo.utcoffset(utc_time) is not None
pst_time = utc_time.astimezone(timezone('US/Pacific'))
is_summary_time = bool(pst_time.dst())
print('is it a summary time? %s.' % is_summary_time)
print('pst time is %s.' % pst_time.strftime('%Y-%m-%d %H:%M:%S'))
if __name__ == '__main__':
get_current_pst_time()
convert_pst_time_to_utc_time('2019-12-03 02:00:00') # pst冬令时转utc
convert_pst_time_to_utc_time('2020-07-03 02:00:00') # pst夏令时转utc
convert_utc_time_to_pst_time('2019-12-03 10:00:00') # utc转pst冬令时
convert_utc_time_to_pst_time('2020-07-03 09:00:00') # utc转pst夏令时
------------(1) Current time to PST time----------------
is it a summary time? True.
local time is 2020-07-13 21:50:34.
utc time is 2020-07-13 13:50:34.
pst time is 2020-07-13 06:50:34.
------------(2) PST time to UTC time----------------
pst time is 2019-12-03 02:00:00.
is it a summary time? False.
utc time is 2019-12-03 10:00:00.
------------(2) PST time to UTC time----------------
pst time is 2020-07-03 02:00:00.
is it a summary time? True.
utc time is 2020-07-03 09:00:00.
------------(3) UTC time to PST time----------------
utc time is 2019-12-03 10:00:00.
is it a summary time? False.
pst time is 2019-12-03 02:00:00.
------------(3) UTC time to PST time----------------
utc time is 2020-07-03 09:00:00.
is it a summary time? True.
pst time is 2020-07-03 02:00:00.
