data : indexable object, optional
            An object with labelled data. If given, provide the label names to
            plot in *x* and *y*, e.g.::

                ax.fill("time", "signal",
                        data={"time": [0, 1, 2], "signal": [0, 1, 0]})

        Returns
        -------
        list of `~matplotlib.patches.Polygon`

        Other Parameters
        ----------------
        **kwargs : `~matplotlib.patches.Polygon` properties

        Notes
        -----
        Use :meth:`fill_between` if you would like to fill the region between
        two curves.
        r¸