code: def test_lstm_forward(pretrain_file):
      model = build_model(pretrain_file)
      run_forward_checks(model, num_states=1)
      run_forward_checks(model, num_states=2)
  
imports: import os
  import pytest
  import torch
  from stanza.models.common import pretrain
  from stanza.models.common.utils import set_random_seed
  from stanza.models.constituency import parse_transitions
  from stanza.tests import *
  from stanza.tests.constituency import test_parse_transitions
  from stanza.tests.constituency.test_trainer import build_trainer
label_desc: Use image node_id 14 for calling a global function with example usage: test_lstm_forward(pretrain_file) without return types