code: def transparency(self):
          
          if 'vertex_colors' in self._data:
              a_min = self._data['vertex_colors'][:, 3].min()
          elif 'face_colors' in self._data:
              a_min = self._data['face_colors'][:, 3].min()
          else:
              return False
  
          return bool(a_min < 255)
docs: Does the current object contain any transparency.
  
          Returns
          ----------
          transparency: bool, does the current visual contain transparency