code: def _get_transitions(self, indexes):
          
          transition_tensors = self.backend.get_transitions(indexes)
  
          return Trajectories(
              num_steps=indexes.shape[0],
              num_envs=indexes.shape[1],
              environment_information=None,
              transition_tensors=transition_tensors,
              rollout_tensors={}
          ).to_transitions()
docs: Return batch with given indexes