class_docstr: Base class for Factors. Any Factor implementation should inherit this class.
class_docstr_tok: ["Base","class","for","Factors",".","Any","Factor","implementation","should","inherit","this","class","."]
code: def is_valid_cpd(self):
      pass
  
file_path: pgmpy/pgmpy/factors/base.py
imports: from abc import abstractmethod
  from functools import reduce
  from itertools import chain
  from opt_einsum import contract
label_desc: Use image node_id 2 for calling the BaseFactor obj's underlying member method code with example usage: obj.is_valid_cpd() without return types