code: def _get_fb_device(self):
          
  
          device = None
  
          for fb in glob.glob('/sys/class/graphics/fb*'):
              name_file = os.path.join(fb, 'name')
              if os.path.isfile(name_file):
                  with open(name_file, 'r') as f:
                      name = f.read()
                  if name.strip() == self.SENSE_HAT_FB_NAME:
                      fb_device = fb.replace(os.path.dirname(fb), '/dev')
                      if os.path.exists(fb_device):
                          device = fb_device
                          break
  
          return device
docs: Internal. Finds the correct frame buffer device for the sense HAT
          and returns its /dev name.