code: def test_forward_pass_runs_correctly(self):
      batch = Batch(self.instances)
      batch.index_instances(self.vocab)
      training_tensors = batch.as_tensor_dict()
      output_dict = self.model(**training_tensors)
  
      metrics = self.model.get_metrics(reset=True)
      # We've set up the data such that there's a fake answer that consists of the whole
      # paragraph.  _Any_ valid prediction for that question should produce an F1 of greater than
      # zero, while if we somehow haven't been able to load the evaluation data, or there was an
      # error with using the evaluation script, this will fail.  This makes sure that we've
      # loaded the evaluation data correctly and have hooked things up to the official evaluation
      # script.
      assert metrics["f1"] > 0
  
      span_start_probs = output_dict["span_start_probs"][0].data.numpy()
      span_end_probs = output_dict["span_start_probs"][0].data.numpy()
      assert_almost_equal(numpy.sum(span_start_probs, -1), 1, decimal=6)
      assert_almost_equal(numpy.sum(span_end_probs, -1), 1, decimal=6)
      span_start, span_end = tuple(
          output_dict["best_span"][0].data.numpy()
      )
      assert span_start >= 0
      assert span_start <= span_end
      assert (
          span_end
          < self.instances[0].fields["passage"].sequence_length()
      )
      assert isinstance(output_dict["best_span_str"][0], unicode)
  
imports: from __future__ import with_statement
  from __future__ import division
  from __future__ import absolute_import
  from flaky import flaky
  import pytest
  import numpy
  from numpy.testing import assert_almost_equal
  import torch
  from allennlp.common import Params
  from allennlp.common.checks import ConfigurationError
  from allennlp.common.testing import ModelTestCase
  from allennlp.data import DatasetReader, Vocabulary
  from allennlp.data.dataset import Batch
  from allennlp.models import BidirectionalAttentionFlow, Model
label_desc: Use image node_id 2 for calling the BidirectionalAttentionFlowTest obj's underlying member method code with example usage: obj.test_forward_pass_runs_correctly() without return types