code: def testMicroCompressionRatio(self):
      fr_micro_compression = self.metrics._get_micro_compression_ratio(
          self.info_dict["fr"]
      )
      self.assertEqual(fr_micro_compression, 3)
  
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 3 for calling the CalculateMetricsTest obj's underlying member method code with example usage: obj.testMicroCompressionRatio() without return types