code: def testEmptyTags(self):
      result = MetadataReader(
          filename=join(self.audioDir, "empty.mp3")
      )()
  
      self.assertEqualVector(result[:7], ("", "", "", "", "", "", ""))
      self.assertTrue(result[7].descriptorNames() == [])
      self.assertEqual(result[8], 0)
  
file_path: essentia/test/src/unittests/io/test_metadatareader.py
imports: from essentia_test import *
  import os
label_desc: Use image node_id 9 for calling the TestMetadataReader obj's underlying member method code with example usage: obj.testEmptyTags() without return types