timezone of GSSHA model

def timezone(self):
        """
        timezone of GSSHA model
        """
        if self._tz is None:
            # GET CENTROID FROM GSSHA GRID
            cen_lat, cen_lon = self.centerLatLon()
            # update time zone
            tf = TimezoneFinder()
            tz_name = tf.timezone_at(lng=cen_lon, lat=cen_lat)

            self._tz = timezone(tz_name)
        return self._tz