code: def testFilterInputWords(self, word_counts, expected_counts):
      allowed_chars = {"a", "b", "c", "d", "e", "f", "g", "h", "i", "j"}
      max_input_tokens = 4
      filtered_counts = learner.filter_input_words(
          word_counts, allowed_chars, max_input_tokens
      )
      self.assertEqual(filtered_counts, expected_counts)
  
imports: import collections
  import logging
  from absl.testing import absltest
  from absl.testing import parameterized
  import numpy
  from tensorflow.python.data.ops import dataset_ops
  from tensorflow.python.ops.ragged import ragged_string_ops
  from tensorflow_text.tools.wordpiece_vocab import wordpiece_tokenizer_learner_lib
label_desc: Use image node_id 1 for calling the FilterInputWordsTest obj's underlying member method code with example usage: obj.testFilterInputWords(word_counts, expected_counts) without return types