Draw guide

        Returns
        -------
        out : matplotlib.offsetbox.Offsetbox
            A drawing of this legend

def draw(self):
        """
        Draw guide

        Returns
        -------
        out : matplotlib.offsetbox.Offsetbox
            A drawing of this legend
        """
        obverse = slice(0, None)
        reverse = slice(None, None, -1)
        width = self.barwidth
        height = self.barheight
        nbars = len(self.bar)
        length = height
        direction = self.direction
        colors = self.bar['color'].tolist()
        labels = self.key['label'].tolist()
        themeable = self.theme.figure._themeable

        # When there is more than one guide, we keep
        # record of all of them using lists
        if 'legend_title' not in themeable:
            themeable['legend_title'] = []
        if 'legend_text_colorbar' not in themeable:
            themeable['legend_text_colorbar'] = []

        # .5 puts the ticks in the middle of the bars when
        # raster=False. So when raster=True the ticks are
        # in between interpolation points and the matching is
        # close though not exactly right.
        _from = self.bar['value'].min(), self.bar['value'].max()
        tick_locations = rescale(self.key['value'],
                                 (.5, nbars-.5),
                                 _from) * length/nbars

        if direction == 'horizontal':
            width, height = height, width
            length = width

        if self.reverse:
            colors = colors[::-1]
            labels = labels[::-1]
            tick_locations = length - tick_locations[::-1]

        # title #
        title_box = TextArea(self.title,
                             textprops=dict(color='black'))
        themeable['legend_title'].append(title_box)

        # colorbar and ticks #
        da = ColoredDrawingArea(width, height, 0, 0)
        if self.raster:
            add_interpolated_colorbar(da, colors, direction)
        else:
            add_segmented_colorbar(da, colors, direction)

        if self.ticks:
            _locations = tick_locations
            if not self.draw_ulim:
                _locations = _locations[:-1]

            if not self.draw_llim:
                _locations = _locations[1:]

            add_ticks(da, _locations, direction)

        # labels #
        if self.label:
            labels_da, legend_text = create_labels(da, labels,
                                                   tick_locations,
                                                   direction)
            themeable['legend_text_colorbar'].extend(legend_text)
        else:
            labels_da = ColoredDrawingArea(0, 0)

        # colorbar + labels #
        if direction == 'vertical':
            packer, align = HPacker, 'bottom'
            align = 'center'
        else:
            packer, align = VPacker, 'right'
            align = 'center'
        slc = obverse if self.label_position == 'right' else reverse
        if self.label_position in ('right', 'bottom'):
            slc = obverse
        else:
            slc = reverse
        main_box = packer(children=[da, labels_da][slc],
                          sep=self._label_margin,
                          align=align,
                          pad=0)

        # title + colorbar(with labels) #
        lookup = {
            'right': (HPacker, reverse),
            'left': (HPacker, obverse),
            'bottom': (VPacker, reverse),
            'top': (VPacker, obverse)}
        packer, slc = lookup[self.title_position]
        children = [title_box, main_box][slc]
        box = packer(children=children,
                     sep=self._title_margin,
                     align=self._title_align,
                     pad=0)
        return box