def METHOD_NAME(
    self, dt: date, name: str = "", since: int = 2014, include_sat: bool = True
) -> None:
    """Add alternative holiday on first day from the date provided
    that's not already a another holiday nor a weekend.
    :param dt:
       The date of the holiday.
    :param name:
       The name of the holiday.
    :param since:
       Year starting from which alt holiday should be added
    :param include_sat:
       Whether Saturday is to be considered a weekend in addition to
       Sunday.
    """
    if not self.observed:
        return None
    target_weekday = {SUN}
    if include_sat:
        target_weekday.add(SAT)
    if (dt.weekday() in target_weekday or len(self.get_list(dt)) > 1) and dt.year >= since:
        obs_date = dt + td(days=+1)
        while obs_date.weekday() in target_weekday or obs_date in self:
            obs_date += td(days=+1)
        for name in (name,) if name else self.get_list(dt):
            if "Alternative holiday" not in name:
                self._add_holiday("Alternative holiday for %s" % name, obs_date)