code: def setUp(self):
      filename = datapath("alldata-id-10.txt")
      train_docs = read_sentiment_docs(filename)
      self.train_docs = train_docs
      self.source_doc_vec = Doc2Vec(
          documents=train_docs[:5], vector_size=8, epochs=50, seed=1
      )
      self.target_doc_vec = Doc2Vec(
          documents=train_docs, vector_size=8, epochs=50, seed=2
      )
  
imports: from collections import namedtuple
  import unittest
  import logging
  import numpy
  import pytest
  from scipy.spatial.distance import cosine
  from gensim.models.doc2vec import Doc2Vec
  from gensim import utils
  from gensim.models import translation_matrix
  from gensim.models import KeyedVectors
  from gensim.test.utils import datapath, get_tmpfile
label_desc: Use image node_id 1 for calling the TestBackMappingTranslationMatrix obj's underlying member method code with example usage: obj.setUp() without return types