从给定的星期和月份计算日期，但可变年份(例如，"x“年中8月的第三个星期日)

import datetime

def find_nth_weekday(year, month, weekday, n):
    # 第一个星期日是月份的第一天或者之后的某一天
    first_day_of_month = datetime.date(year, month, 1)
    first_weekday_of_month = first_day_of_month.weekday()  # 星期一为0，星期日为6
    
    # 计算第一个目标星期日是哪一天
    days_to_first_weekday = (weekday - first_weekday_of_month) % 7
    if days_to_first_weekday == 0 and first_day_of_month.weekday() == weekday:
        first_target_weekday = first_day_of_month
    else:
        first_target_weekday = first_day_of_month + datetime.timedelta(days=days_to_first_weekday)
    
    # 计算第n个目标星期日
    nth_target_weekday = first_target_weekday + datetime.timedelta(weeks=n-1)
    
    return nth_target_weekday

# 示例：计算2023年8月的第三个星期日
year = 2023
month = 8
weekday = 6  # 星期日为6
n = 3
date = find_nth_weekday(year, month, weekday, n)
print(date)  # 输出: 2023-08-20