def METHOD_NAME(self, X, y=None, sample_weight=None):
    self.x = X
    self.y = y
    self.w = sample_weight
    if self.x is None:
        self.infer_x_w()
    if self.thru_orig:
        self._fit_OLS_thru_orig()
    else:
        self._fit_OLS()
    return self