求前N天，或者N天前后日期
import datetime
# 获取前1天或N天的日期，beforeOfDay=1：前1天；beforeOfDay=N：前N天
def getdate(self,beforeOfDay):
today = datetime.datetime.now()
# 计算偏移量
offset = datetime.timedelta(days=-beforeOfDay)
# 获取想要的日期的时间
re_date = (today + offset).strftime('%Y-%m-%d')
return re_date
# 获取前一周的所有日期(weeks=1)，获取前N周的所有日期(weeks=N)
def getBeforeWeekDays(self,weeks=1):
# 0,1,2,3,4,5,6,分别对应周一到周日
week = datetime.datetime.now().weekday()
days_list = []
start = 7 * weeks + week
end = week
for index in range(start, end, -1):
day =self.getdate(index) print(day)
#测试
#getBeforeWeekDays(1)