python 时间库的用法 时区的转化

1. 月份的加减

　　https://blog.csdn.net/qq_18863573/article/details/79444094

　　第三方模块：python-dateutil

import datetime
from dateutil.relativedelta import relativedelta  

datetime_now = datetime.datetime.now()
datetime_three_month_ago = datetime_now - relativedelta(months=3)
print datetime_three_month_ago

2.Python 获取起止日期段中的时间列表（工作日）

　

import pandas
def gain_weekend_date_list(start_date, end_date):
    """获取指定时间内的周末"""
    SUN_list = [d.strftime("%Y-%m-%d") for d in pandas.date_range(start_date, end_date, freq="W")]
    SAT_list = [d.strftime("%Y-%m-%d") for d in pandas.date_range(start_date, end_date, freq="W-SAT")]
    return SAT_list + SUN_list

　https://my.oschina.net/u/942203/blog/1623083

3.给获取的时间 添加时区

https://www.rapospectre.com/blog/24

https://juejin.im/post/5848b301128fe1006907d5ed

import datetime
import pytz

now_time_utc = datetime.datetime.utcnow()
now_time_utc=now_time_utc.replace(tzinfo=pytz.timezone('UTC'))

4.datetime日期的格式化输出（strfitime）

import datetime
datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S');
'2018-05-17 08:06:17'

　　

>>> datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S');

'2013-09-17 08:06:17'