code: def testMicroDroppedCharPercent(self):
      en_micro_dropped_char = (
          self.metrics._get_micro_dropped_char_percent(
              self.info_dict["en"]
          )
      )
      self.assertEqual(en_micro_dropped_char, 100 / 13)
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import collections
  import logging
  import tempfile
  from absl.testing import absltest
  import apache_beam
  from apache_beam.testing.test_pipeline import TestPipeline
  from apache_beam.testing.util import assert_that
  from apache_beam.testing.util import equal_to
  import tensorflow.compat.v1
  from tensorflow_text.tools.wordpiece_vocab import utils
label_desc: Use image node_id 5 for calling the CalculateMetricsTest obj's underlying member method code with example usage: obj.testMicroDroppedCharPercent() without return types