code: def pause_trial(self, trial):
          
  
          trial_future = self._find_item(self._running, trial)
          if trial_future:
              self._paused[trial_future[0]] = trial
          super(RayTrialExecutor, self).pause_trial(trial)
docs: Pauses the trial.
  
          If trial is in-flight, preserves return value in separate queue
          before pausing, which is restored when Trial is resumed.