在时间上向后移动，直到python中具有给定频率(月)的特定日期

from datetime import datetime, timedelta

def dates_before_specific_date(start_date, frequency_months):
    current_date = start_date
    dates = []
    
    while current_date.month > start_date.month - frequency_months:
        dates.append(current_date)
        # 计算下一个月的同一天
        if current_date.month == 12:
            next_month = current_date.replace(year=current_date.year + 1, month=1)
        else:
            try:
                next_month = current_date.replace(month=current_date.month + 1)
            except ValueError:
                # 处理闰年2月的情况
                next_month = current_date.replace(year=current_date.year + 1, month=current_date.month + 1 - 12)
        
        current_date = next_month
    
    return dates

# 示例使用
start_date = datetime(2023, 5, 15)
frequency_months = 5
result_dates = dates_before_specific_date(start_date, frequency_months)
for date in result_dates:
    print(date.strftime('%Y-%m-%d'))