code: def test_single_while(self, n, type_, target):
      if (not n) and (
          (
              target
              in (
                  unconditional_return_in_single_while,
                  effectively_unconditional_return_in_single_while,
              )
          )
      ):
          self.skipTest(
              "Undefined symbols require at least one iteration."
          )
  
      n = type_(n)
      self.assertFunctionMatchesEager(target, n)
  
imports: import itertools
  from absl.testing import parameterized
  import tensorflow
  from tensorflow.python.autograph.tests import reference_test_base
label_desc: Use image node_id 2 for calling the LoopControlFlowTest obj's underlying member method code with example usage: obj.test_single_while(n, type_, target) without return types