code: def test_readahead_file_path(self):
      self.assertEqual(
          "foo/bar", platform_util.readahead_file_path("foo/bar")
      )
  
imports: from tensorboard import test
  from tensorboard.util import platform_util
label_desc: Use image node_id 1 for calling the PlatformUtilTest obj's underlying member method code with example usage: obj.test_readahead_file_path() without return types