code: def test_subscript(self):
      class TestClass(object):
          def __init__(self):
              self.v = 1
  
          def __add__(self, other):
              self.v += other
              return self
  
          def __getitem__(self, _):
              return self.v
  
      def f(l):
          return l[0]
  
      tc = TestClass()
      tr = self.transform_with_test_ld(f)
  
      self.assertEqual(tr(tc), 2)
  
file_path: tensorflow-upstream/tensorflow/python/autograph/converters/variables_test.py
imports: from tensorflow.python.autograph.converters import variables
  from tensorflow.python.autograph.core import converter_testing
  from tensorflow.python.platform import test
label_desc: Use image node_id 13 for calling the VariablesTest obj's underlying member method code with example usage: obj.test_subscript() and returns: l, self, self