code: def test_singleton_redefinition():
      class TestSingleton(Basic, metaclass=Singleton):
          pass
  
      assert TestSingleton() is S.TestSingleton
  
      class TestSingleton(Basic, metaclass=Singleton):
          pass
  
      assert TestSingleton() is S.TestSingleton
  
imports: from sympy.core.basic import Basic
  from sympy.core.numbers import Rational
  from sympy.core.singleton import S, Singleton
label_desc: Use image node_id 2 for calling a global function with example usage: test_singleton_redefinition() without return types