code: def test_read(self):
      def f(l):
          return l
  
      tr = self._transform_with_test_ld(f)
  
      self.assertEqual(tr(1), 2)
  
file_path: DALI/dali/test/python/autograph/converters/test_variables.py
imports: from nvidia.dali._autograph.converters import variables
  from nvidia.dali._autograph.core import converter_testing
label_desc: Use image node_id 2 for calling the VariablesTest obj's underlying member method code with example usage: obj.test_read() and returns: l