code: def tf():
      """Provide the root module of a TF-like API for use within TensorBoard.
  
      By default this is equivalent to `import tensorflow as tf`, but it can be used
      in combination with //tensorboard/compat:tensorflow (to fall back to a stub TF
      API implementation if the real one is not available) or with
      //tensorboard/compat:no_tensorflow (to force unconditional use of the stub).
  
      Returns:
        The root module of a TF-like API, if available.
  
      Raises:
        ImportError: if a TF-like API is not available.
      """
      try:
          from tensorboard.compat import notf  # noqa: F401
      except ImportError:
          try:
              import tensorflow
  
              return tensorflow
          except ImportError:
              pass
      from tensorboard.compat import tensorflow_stub
  
      return tensorflow_stub
  
label_desc: Use image node_id 1 for calling a global function with example usage: tf() and returns: tensorflow_stub, tensorflow