#!/usr/bin/env python

-- coding:utf-8 --
import datetime
import collections
def date_list_fun(starttime,endtime):
    '''計算輸入的起始日期和結束日期之間的所有日期'''
    _u=datetime.timedelta(days=1)
    startdate=datetime.datetime.strptime(starttime,'%Y%m%d')
    enddate=datetime.datetime.strptime(endtime,'%Y%m%d')
    n=0
    date_list=[]
    if  startdate<=enddate:

    # print startdate,enddate
    while 1:
        _time=startdate+n*_u
        date_list.append(_time.strftime('%Y%m%d'))
        n=n+1
        if _time==enddate:
            break
return date_list

def allweeks(year):
    '''計算一年內所有周的具體日期,從1月1號開始，12.31號結束
    輸出如{1: ['20190101','20190106'],...} 只有六天
    '''
    start_date=datetime.datetime.strptime(str(year)+'0101','%Y%m%d')
    end_date=datetime.datetime.strptime(str(year)+'1231','%Y%m%d')
    _u=datetime.timedelta(days=1)
    n=0
    week_date={}
    while 1:
        _time=start_date+n*_u
        w=str(int(_time.strftime('%W'))+1)
        week_date.setdefault(w,[]).append(_time.strftime('%Y%m%d'))
        n=n+1
        if _time==end_date:
            break
    week_date_start_end={}
    for i in week_date:
       week_date_start_end[i]=[week_date[i][0],week_date[i][-1]]
    print   week_date
    print week_date_start_end
    return week_date
def all_weeks(year):
    '''計算一年內所有周的具體日期,每周都是7天，可能最后一周到 下年
     week_date 輸出如{1: ['20181231', '20190101', '20190102', '20190103', '20190104', '20190105', '20190106'],...}
     計算一年內所有周的起始日期
     week_date_start_end {1: ['20181231','20190106'],...}
     '''

start_date=datetime.datetime.strptime(str(int(year)-1)+'1224','%Y%m%d')
end_date=datetime.datetime.strptime(str(int(year)+1)+'0107','%Y%m%d')
_u=datetime.timedelta(days=1)
n=0
week_date={}
while 1:
    _time=start_date+n*_u
    y,w=_time.isocalendar()[:2]
    if y==year :
        week_date.setdefault(w,[]).append(_time.strftime('%Y%m%d'))
    n=n+1
    if _time==end_date:
        break
week_date_start_end={}
for i in week_date:
   week_date_start_end[i]=[week_date[i][0],week_date[i][-1]]
print   week_date
# print week_date_start_end
return week_date,week_date_start_end</pre>