python中实现days360函数

# -*- coding: utf-8 -*-
"""
Created on Fri Sep 23 20:42:58 2022
@author: Administrator
"""
import time
import datetime

def days360(start_date, end_date, method_eu=False):
    """
    功能：同excel中函数，=DAYS360(B452,A452,0)
    """
    start_date = datetime.datetime.strptime(start_date,"%Y-%m-%d")
    end_date = datetime.datetime.strptime(end_date,"%Y-%m-%d") 
    start_day = start_date.day
    start_month = start_date.month
    start_year = start_date.year
    end_day = end_date.day
    end_month = end_date.month
    end_year = end_date.year

    if (
        start_day == 31 or
        (
            method_eu is False and
            start_month == 2 and (
                start_day == 29 or (
                    start_day == 28 and
                    ((start_year%4==0) and (start_year%100 !=0) or (start_year%400)==0) #闰年
                )
            )
        )
    ):
        start_day = 30
    if end_day == 31:
        if method_eu is False and start_day != 30:
            end_day = 1

            if end_month == 12:
                end_year += 1
                end_month = 1
            else:
                end_month += 1
        else:
            end_day = 30

    return (
        end_day + end_month * 30 + end_year * 360 -
        start_day - start_month * 30 - start_year * 360)

days360('2020-02-28','2021-02-22')