from calendar import monthrange
from datetime import date


def add_months_ymd(value: date, months: int) -> date:
    year = value.year + (value.month - 1 + months) // 12
    month = (value.month - 1 + months) % 12 + 1
    last_day = monthrange(year, month)[1]
    return date(year, month, min(value.day, last_day))


def ymd_int(value: date) -> int:
    return int(value.strftime("%Y%m%d"))


def ymd_month_str(value: date) -> str:
    return value.strftime("%Y-%m")