code: def components(self, visible=True):
          
          if self._on:
              self._quality.append_on_chord(self.on, self.root)
  
          return self._quality.get_components(root=self._root, visible=visible)
docs: Return the component notes of chord
  
          :param bool visible: returns the name of notes if True else list of int
          :rtype: list[(str or int)]
          :return: component notes of chord