def choropleth(self, *args, **kwargs):
        """Call the Choropleth class with the same arguments.

        This method may be deleted after a year from now (Nov 2018).
        """
        warnings.warn(
            'The choropleth  method has been deprecated. Instead use the new '
            'Choropleth class, which has the same arguments. See the example '
            'notebook \'GeoJSON_and_choropleth\' for how to do this.',
            FutureWarning
        )
        from folium.features import Choropleth
        self.add_child(Choropleth(*args, **kwargs))