code: def _is_not_pickle_safe_gl_model_class(obj_class):
      
      if issubclass(obj_class, _toolkits._model.CustomModel):
          return not obj_class._is_gl_pickle_safe()
      return False
docs: Check if a Turi create model is pickle safe.
  
      The function does it by checking that _CustomModel is the base class.
  
      Parameters
      ----------
      obj_class    : Class to be checked.
  
      Returns
      ----------
      True if the GLC class is a model and is pickle safe.