def add_holidays(
        self,
        country_code: str,
        prov: str = None,
        state: str = None,
        tz: Optional[str] = None,
    ) -> Self:
        """
        Adds a binary univariate component to the current series that equals 1 at every index that
        corresponds to selected country's holiday, and 0 otherwise.

        The frequency of the TimeSeries is daily.

        Available countries can be found `here <https://github.com/dr-prodigy/python-holidays#available-countries>`_.

        This works only for deterministic time series (i.e., made of 1 sample).

        Parameters
        ----------
        country_code
            The country ISO code
        prov
            The province
        state
            The state
        tz
            Optionally, a time zone to convert the time index to before computing the attributes.

        Returns
        -------
        TimeSeries
            A new TimeSeries instance, enhanced with binary holiday component.
        """
        self._assert_deterministic()
        from darts.utils import timeseries_generation as tg

        return self.stack(
            tg.holidays_timeseries(
                self.time_index,
                country_code=country_code,
                prov=prov,
                state=state,
                tz=tz,
            )
        )

        Adds a binary univariate component to the current series that equals 1 at every index that
        corresponds to selected country's holiday, and 0 otherwise.

        The frequency of the TimeSeries is daily.

        Available countries can be found `here <https://github.com/dr-prodigy/python-holidays#available-countries>`_.

        This works only for deterministic time series (i.e., made of 1 sample).

        Parameters
        ----------
        country_code
            The country ISO code
        prov
            The province
        state
            The state
        tz
            Optionally, a time zone to convert the time index to before computing the attributes.

        Returns
        -------
        TimeSeries
            A new TimeSeries instance, enhanced with binary holiday component.
        
darts/timeseries.py