format.md

Symbol	Meaning	Example
%a	Abbreviated weekday name	'Wed'
%A	Full weekday name	'Wednesday'
%w	Weekday number: 0 (Sunday) through 6 (Saturday)	'3'
%d	Day of the month (zero padded)	'13'
%b	Abbreviated month name	'Jan'
%B	Full month name	'January'
%m	Month of the year	'01'
%y	Year without century	'18'
%Y	Year with century	'2018'
%H	Hour from 24-hour clock	'17'
%I	Hour from 12-hour clock	'05'
%p	AM/PM	'PM'
%M	Minutes	'00'
%S	Seconds	'00'
%f	Microseconds	'000000'
%z	UTC offset for time zone–aware objects	'-0500'
%Z	Time zone name	'EST'
%j	Day of the year	'013'
%W	Week of the year	'02'
%c	Date and time representation for the current locale	'Wed Jan 13 17:00:00 2016'
%x	Date representation for the current locale	'01/13/16'
%X	Time representation for the current locale	'17:00:00'
%%	A literal % character	'%'

GMT.py

# GMT 时间格式
GMT_FORMAT =  '%a, %d %b %Y %H:%M:%S GMT'

stftime.py

# 时间对象 转字符串
from datetime import datetime 
datetime.strftime(datetime.now(),"%Y-%m-%d %H:%M:%S")

strptime.py

# 字符串对象转时间对象
from datetime import datetime 
>>> datetime.strptime('2018-09-09',"%Y-%m-%d")
datetime.datetime(2018, 9, 9, 0, 0)

us.py

# 美国时间 和 UTC 时间 转换
datetime.strftime(datetime.utcnow()-timedelta(hours=8),'%Y-%m-%d %H:%M:%S')