1. import datetime
    3. def days(start,end):
    4.     start_day = datetime.datetime.strptime(start,"%Y-%m-%d")
    5.     end_day = datetime.datetime.strptime(end,"%Y-%m-%d")
    6.     num = (end_day - start_day).days
    7.     return num
    9. def months(start,end):
    10.     start_year = datetime.datetime.strptime(start,"%Y-%m-%d").year
    11.     end_year = datetime.datetime.strptime(end,"%Y-%m-%d").year
    12.     start_month = datetime.datetime.strptime(start,"%Y-%m-%d").month
    13.     end_month = datetime.datetime.strptime(end,"%Y-%m-%d").month
    14.     num = (end_year-start_year) * 12 + (end_month-start_month)
    15.     return num
    17. d = days('2019-11-19','2021-01-20') # 1
    18. print("day_nums: ",d)
    19. m = months('2019-10-11','2019-12-11') # 2