'Returns the amount of space one should reserve for text
above and below the axes.  Returns a tuple (above, below)'

def get_text_heights(self, renderer):

    (bbox, bbox2) = self.get_ticklabel_extents(renderer)
    padPixels = self.majorTicks[0].get_pad_pixels()
    above = 0.0
    if bbox2.height:
        above += (bbox2.height + padPixels)
    below = 0.0
    if bbox.height:
        below += (bbox.height + padPixels)
    if (self.get_label_position() == u'top'):
        above += (self.label.get_window_extent(renderer).height + padPixels)
    else:
        below += (self.label.get_window_extent(renderer).height + padPixels)
    return (above, below)
