def METHOD_NAME(self, y, X=None, update_params=False):
    """Update fitted paramters and performs a new ensemble fit.
    Parameters
    ----------
    y : pd.Series
    X : pd.DataFrame
    update_params : bool, optional (default=False)
    Returns
    -------
    self : an instance of self
    """
    if len(y) >= 1 and self.ensemble_algorithm is not None:
        self._fit_ensemble(y, X)
    for forecaster in self.forecasters_:
        forecaster.update(y, X, update_params=update_params)
    return self