code: def test_crf_log_norm_zero_seq_length(dtype):
      """Test `crf_log_norm` when `sequence_lengths` contains one or more
      zeros."""
      inputs = tf.constant(np.ones([2, 10, 5], dtype=dtype))
      transition_params = tf.constant(np.ones([5, 5], dtype=dtype))
      sequence_lengths = tf.constant(np.zeros([2], dtype=np.int32))
      expected_log_norm = np.zeros([2], dtype=dtype)
      log_norm = crf_log_norm(
          inputs, sequence_lengths, transition_params
      )
      np.testing.assert_allclose(log_norm, expected_log_norm)
  
file_path: rasa/tests/utils/tensorflow/test_crf.py
imports: import itertools
  import pytest
  import numpy
  import tensorflow
  from rasa.utils.tensorflow.crf import crf_sequence_score, crf_unary_score, crf_binary_score, crf_log_norm, crf_log_likelihood
label_desc: Use image node_id 7 for calling a global function with example usage: test_crf_log_norm_zero_seq_length(dtype) without return types