Computes padding along the axes taking into account the plot aspect.

def get_padding(self, extents):
        """
        Computes padding along the axes taking into account the plot aspect.
        """
        (x0, y0, z0, x1, y1, z1) = extents
        padding = 0 if self.overlaid else self.padding
        xpad, ypad, zpad = get_axis_padding(padding)
        if not self.overlaid and not self.batched:
            xspan = x1-x0 if util.is_number(x0) and util.is_number(x1) else None
            yspan = y1-y0 if util.is_number(y0) and util.is_number(y1) else None
            aspect = self.get_aspect(xspan, yspan)
            if aspect > 1:
                xpad = tuple(xp/aspect for xp in xpad) if isinstance(xpad, tuple) else xpad/aspect
            else:
                ypad = tuple(yp*aspect for yp in ypad) if isinstance(ypad, tuple) else ypad*aspect
        return xpad, ypad, zpad