code: def test_file_instruction_dirname(self, filename, expected):
      file_instruction = shard_utils.FileInstruction(filename, 0, -1, 1)
      self.assertEqual(file_instruction.dirname(), expected)
  
imports: from absl.testing import parameterized
  from tensorflow_datasets import testing
  from tensorflow_datasets.core.utils import shard_utils
label_desc: Use image node_id 7 for calling the GetReadInstructionsTest obj's underlying member method code with example usage: obj.test_file_instruction_dirname(filename, expected) without return types