docstr: Current mini-batch task labels.
code: def mb_task_id(self):
      """Current mini-batch task labels."""
      mbatch = self.mbatch
      assert mbatch is not None
      assert len(mbatch) >= 3
      return mbatch[-1]
  
file_path: avalanche/avalanche/training/templates/problem_type/supervised_problem.py
imports: from avalanche.models import avalanche_forward
  from avalanche.training.templates.strategy_mixin_protocol import SupervisedStrategyProtocol
label_desc: Use image node_id 3 for calling the SupervisedProblem obj's underlying member method code with example usage: obj.mb_task_id() and returns: mbatch