code: def _transition_steps(self, brightness=None):
          
          if brightness is not None:
              self._assert_is_brightness(brightness)
              return self._driver.steps(self.brightness, brightness)
  
          return 0
docs: Get the maximum number of steps needed for a transition.
  
          :param brightness: The brightness to transition to (0.0-1.0).
          :return: The maximum number of steps.