docstr: Test a multistage training for a few iterations on the fake data
  
  This should start with no pattn or lattn, have pattn in the middle, then lattn at the end
docstr_tok: ["Test","a","multistage","training","for","a","few","iterations","on","the","fake","data","This","should","start","with","no","pattn","or","lattn",",","have","pattn","in","the","middle",",","then","lattn","at","the","end"]
code: def test_multistage_lattn(self, wordvec_pretrain_file):
      """
      Test a multistage training for a few iterations on the fake data
  
      This should start with no pattn or lattn, have pattn in the middle, then lattn at the end
      """
      with tempfile.TemporaryDirectory(
          dir=TEST_WORKING_DIR
      ) as tmpdirname:
          self.run_multistage_tests(
              wordvec_pretrain_file, tmpdirname, use_lattn=True
          )
  
imports: from collections import defaultdict
  import logging
  import pathlib
  import tempfile
  import pytest
  import torch
  from torch import optim
  from stanza import Pipeline
  from stanza.models import constituency_parser
  from stanza.models.common import pretrain
  from stanza.models.common.bert_embedding import load_bert, load_tokenizer
  from stanza.models.common.foundation_cache import FoundationCache
  from stanza.models.common.utils import set_random_seed
  from stanza.models.constituency import lstm_model
  from stanza.models.constituency import trainer
  from stanza.models.constituency import tree_reader
  from stanza.tests import *
label_desc: Use image node_id 14 for calling the TestTrainer obj's underlying member method code with example usage: obj.test_multistage_lattn(wordvec_pretrain_file) without return types