Draw legend onto the figure

def _draw_legend(self):
        """
        Draw legend onto the figure
        """
        legend_box = self.guides.build(self)
        if not legend_box:
            return

        figure = self.figure
        left = figure.subplotpars.left
        right = figure.subplotpars.right
        top = figure.subplotpars.top
        bottom = figure.subplotpars.bottom
        W, H = figure.get_size_inches()
        position = self.guides.position
        get_property = self.theme.themeables.property
        # defaults
        spacing = 0.1
        strip_margin_x = 0
        strip_margin_y = 0

        with suppress(KeyError):
            spacing = get_property('legend_box_spacing')
        with suppress(KeyError):
            strip_margin_x = get_property('strip_margin_x')
        with suppress(KeyError):
            strip_margin_y = get_property('strip_margin_y')

        right_strip_width = self.facet.strip_size('right')
        top_strip_height = self.facet.strip_size('top')

        # Other than when the legend is on the right the rest of
        # the computed x, y locations are not gauranteed not to
        # overlap with the axes or the labels. The user must then
        # use the legend_margin theme parameter to adjust the
        # location. This should get fixed when MPL has a better
        # layout manager.
        if position == 'right':
            loc = 6
            pad = right_strip_width*(1+strip_margin_x) + spacing
            x = right + pad/W
            y = 0.5
        elif position == 'left':
            loc = 7
            x = left - spacing/W
            y = 0.5
        elif position == 'top':
            loc = 8
            x = 0.5
            pad = top_strip_height*(1+strip_margin_y) + spacing
            y = top + pad/H
        elif position == 'bottom':
            loc = 9
            x = 0.5
            y = bottom - spacing/H
        else:
            loc = 10
            x, y = position

        anchored_box = AnchoredOffsetbox(
            loc=loc,
            child=legend_box,
            pad=0.,
            frameon=False,
            bbox_to_anchor=(x, y),
            bbox_transform=figure.transFigure,
            borderpad=0.)

        anchored_box.set_zorder(90.1)
        self.figure._themeable['legend_background'] = anchored_box
        ax = self.axs[0]
        ax.add_artist(anchored_box)