python Timestamp、Datetime、UTC时间之间转换练习

#coding=utf-8
import time
import datetime
def get_prev_timestamp(tart_ts, interval = 3):
start_array = datetime.datetime.utcfromtimestamp(start_ts)
start_array = start_array + datetime.timedelta(hours=8)
prev_time = (start_array - datetime.timedelta(days = interval))
prev_ts = int(time.mktime(prev_time.timetuple()))

return prev_ts

def get_end_timestamp(start_ts, interval = 30):
start_date = datetime.datetime.utcfromtimestamp(start_ts)
start_date = start_date + datetime.timedelta(hours=8)
end_date = start_date + datetime.timedelta(minutes = interval)
end_ts = int(time.mktime(end_date.timetuple()))

return end_ts

def get_seven_day_ago( day = 7):
human = {'d':86400 }
now = int(time.time())
ts = now - day * human['d']

return str(ts)

start_ts = time.time()

print get_seven_day_ago()