code: def random_attn(self):
      return torch.randn(
          self.BATCH_SZ * self.BEAM_SZ, 1, self.INP_SEQ_LEN
      )
  
imports: import unittest
  from onmt.translate.beam_search import BeamSearch, GNMTGlobalScorer
  from onmt.translate.beam_search import BeamSearchLM
  from copy import deepcopy
  import torch
label_desc: Use image node_id 1 for calling the TestBeamSearchAgainstReferenceCase obj's underlying member method code with example usage: obj.random_attn() and returns: torch