code: def keras_tensor_to_placeholder(x):
      """Construct a graph placeholder to represent a KerasTensor when tracing."""
      if isinstance(x, KerasTensor):
          return x._to_placeholder()  # pylint: disable=protected-access
      else:
          return x
  
imports: from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import sparse_tensor
  from tensorflow.python.framework import tensor
  from tensorflow.python.framework import tensor_shape
  from tensorflow.python.framework import type_spec
  from tensorflow.python.keras.utils import object_identity
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops.ragged import ragged_operators
  from tensorflow.python.ops.ragged import ragged_tensor
  from tensorflow.python.util import nest
label_desc: Use image node_id 2 for calling a global function with example usage: keras_tensor_to_placeholder(x) and returns: x, x