The remainder keyword needs to be one of 'drop', 'passthrough', or estimator. '%s' was passed instead

Raise code

""" remaining columns.
        """
        is_transformer = ((hasattr(self.remainder, "fit")
                           or hasattr(self.remainder, "fit_transform"))
                          and hasattr(self.remainder, "transform"))
        if (self.remainder not in ('drop', 'passthrough')
                and not is_transformer):
            raise ValueError(
                "The remainder keyword needs to be one of 'drop', "
                "'passthrough', or estimator. '%s' was passed instead" %
                self.remainder)

        self._n_features = X.shape[1]
        cols = set(chain(*self._transformer_to_input_indices.values()))
        remaining = sorted(set(range(self._n_features)) - cols)
        self