我的python歷程--第二天

今天花一个多小时写了一个小函数.用来到得由昨天日期组成的字符串.如果没有20个月的儿子在一边捣蛋,可能会快一些.import timedef before_today():  result = time.strftime("%Y%m%d")  year1 = time.strftime("%Y")  month1 = time.strftime("%m")  day1 = time.strftime("%d")  td = int(day1) - 1  ty = int(year1)  tm = int(month1)  if td == 0:     tm = tm - 1     if str(tm) in ("1","3","5","7","8","10"): td = 31     elif str(tm) in ("4","6","9"):        td = 30     elif tm == 0:        td = 31        tm = 12        ty = ty - 1     elif tm == 2:        if (ty % 4 == 0 and ty % 100 0) or (ty % 400 == 0):           print "is RunNian"           td = 29        else:            print "Not RunNian"            td = 28  if tm      month1 = "0" + str(tm)  else:     month1 = str(tm)  if td      day1 = "0" + str(td)  else:     day1 = str(td)  result = str(ty) + month1 + day1  print result  return resultprint before_today()今天感觉程序的调试排错方面好像不太好.