code: def test_decorator(self):
      @Context(VARIABLE=1, DEBUG=4)
      def test():
          self.assertEqual(VARIABLE.value, 1)
  
      self.assertEqual(VARIABLE.value, 0)
      test()
      self.assertEqual(VARIABLE.value, 0)
  
imports: import unittest
  from PIL import Image
  from tinygrad.helpers import Context, ContextVar, merge_dicts, strip_parens, prod, round_up, fetch, fully_flatten, from_mv, to_mv
  from tinygrad.shape.symbolic import Variable, NumNode
label_desc: Use image node_id 13 for calling the TestContextVars obj's underlying member method code with example usage: obj.test_decorator() without return types