set margins

def set_margins(self, left=0.1, top=0.1, right=0.1, bottom=0.1,
                    delay_draw=False):
        "set margins"
        self.margins = (left, top, right, bottom)
        if self.panel is not None:
            self.panel.gridspec.update(left=left, top=1-top,
                                       right=1-right, bottom=bottom)
        for ax in self.canvas.figure.get_axes():
            ax.update_params()
            ax.set_position(ax.figbox)
        if not delay_draw:
            self.canvas.draw()
        if callable(self.margin_callback):
            self.margin_callback(left=left, top=top, right=right, bottom=bottom)