Python datetime字符串/时间戳相互转换

#datetime转字符串
ex: 
　　now = datetime.datetime.now()
　　time_string = now.strftime('%Y-%m-%d %H:%M:%S')

#字符串转datetime
ex:
　　time_string = '2020-05-26 11:42:54'
　　datetime.datetime.strptime(time_string, "%Y-%m-%d %H:%M:%S")

#字符串转时间戳
ex: 
　　time_string = '2020-05-26 11:42:54'
　　time.mktime(time.strptime(time_string, "%Y-%m-%d %H:%M:%S"))

#时间戳转字符串
ex:
　　stamp = 1590464574.0
　　time.strftime("%Y-%m-%d %H:%M:%S", time.localtime(stamp))

#datetime转时间戳
ex:
　　now = datetime.datetime.now()
　　time.mktime(now.timetuple())