code: def set_rotation(self, r=0, redraw=True):
          
  
          if r in self._pix_map.keys():
              if redraw:
                  pixel_list = self.get_pixels()
              self._rotation = r
              if redraw:
                  self.set_pixels(pixel_list)
          else:
              raise ValueError('Rotation must be 0, 90, 180 or 270 degrees')
docs: Sets the LED matrix rotation for viewing, adjust if the Pi is upside
          down or sideways. 0 is with the Pi HDMI port facing downwards