code: def test_read_features_default_axis(self):
      # TODO(b/123241798): use TEST_TMPDIR
      basedir = tempfile.mkdtemp()
      schema_no_sparse_features = """
      {
        "feature": [{
          "name": "my_key",
          "fixedShape": {},
          "type": "INT",
          "domain": {
            "ints": {}
          },
          "parsingOptions": {
            "tfOptions": {
              "fixedLenFeature": {}
            }
          }
        }]
      }
      """
      self._write_schema_to_disk(basedir, schema_no_sparse_features)
      _ = metadata_io.read_metadata(basedir)
  
file_path: transform/tensorflow_transform/tf_metadata/metadata_io_test.py
imports: import os
  import tempfile
  from tensorflow_transform.tf_metadata import test_common
  from tensorflow_transform.tf_metadata import dataset_metadata
  from tensorflow_transform.tf_metadata import metadata_io
  import unittest
  from tensorflow.python.lib.io import file_io
label_desc: Use image node_id 3 for calling the SchemaIOv1JsonTest obj's underlying member method code with example usage: obj.test_read_features_default_axis() without return types