code: def __init__(self):
      self.a = Categorical([1, 2, 3], label="a")
      self.b = Categorical([4, 5, 6, 7], label="b")
  
      if current_model() is not None:
          self.a1 = ensure_frozen(self.a)
          self.b1 = ensure_frozen(self.b)
  
file_path: nni/test/ut/nas/space/test_executable_space.py
imports: import sys
  import pytest
  import nni
  from nni.mutable import *
  from nni.mutable.mutable import _mutable_equal
  from nni.nas.evaluator import FunctionalEvaluator, FrozenEvaluator
  from nni.nas.space import *
label_desc: Use image node_id 1 to create a new MyModelSpace object from inherited base classes: BaseModelSpace with example: obj = MyModelSpace()