Return top weights getter for label_id.

def _linear_weights(clf, x, top, flt_feature_names, flt_indices):
    """ Return top weights getter for label_id.
    """
    def _weights(label_id, scale=1.0):
        coef = get_coef(clf, label_id)
        scores = _multiply(x, coef)
        return get_top_features_filtered(x, flt_feature_names, flt_indices,
                                         scores, top, scale)
    return _weights