code: def get_start_end_idx(self):
      start_idx = self.data_parallel_rank * self.local_minibatch_size
      end_idx = start_idx + self.local_minibatch_size
      return start_idx, end_idx
  
imports: import abc
  import torch
label_desc: Use image node_id 3 for calling the MegatronPretrainingSampler obj's underlying member method code with example usage: obj.get_start_end_idx() and returns: start_idx,  end_idx