code: def is_keras_tensor(x):
      """Returns whether `x` is a Keras tensor.
  
      A "Keras tensor" is a *symbolic tensor*, such as a tensor
      that was created via `Input()`. A "symbolic tensor"
      can be understood as a placeholder -- it does not
      contain any actual numerical data, only a shape and dtype.
      It can be used for building Functional models, but it
      cannot be used in actual computations.
      """
      return isinstance(x, KerasTensor)
  
imports: import tree
  from keras.api_export import keras_export
  from keras.utils.naming import auto_name
label_desc: Use image node_id 2 for calling a global function with example usage: is_keras_tensor(x) and returns: isinstance