docstr: Returns True if obj is an encrypted tensor.
code: def is_encrypted_tensor(cls, obj):
      """
      Returns True if obj is an encrypted tensor.
      """
      from fate.arch.protocol.mpc import CrypTensor
  
      return isinstance(obj, CrypTensor)
  
imports: import typing
  import warnings
  from typing import overload
  import torch
  from fate.arch.protocol import mpc
  import logging
label_desc: Use image node_id 9 for calling the MPC obj's underlying member method code with example usage: obj.is_encrypted_tensor(cls, obj) and returns: isinstance