def METHOD_NAME(self, append=True, random_state=None):
    """Make and configure a copy of the `base_estimator_` attribute.
    Warning: This method should be used to properly instantiate new
    sub-estimators.
    """
    estimator = clone(self.base_estimator_)
    estimator.set_params(**dict((p, getattr(self, p))
                                for p in self.estimator_params))
    if random_state is not None:
        _set_random_states(estimator, random_state)
    if append:
        self.estimators_.append(estimator)
    return estimator