code: def test_while_loop(self):
      def f(n):
          i = 0
          s = 0
          while i < n:
              i += 1
              s += i
              if s > 4:
                  return s
          return -1
  
      self.assertTransformedEquivalent(f, 0)
      self.assertTransformedEquivalent(f, 2)
      self.assertTransformedEquivalent(f, 4)
  
imports: from nvidia.dali._autograph.converters import functions
  from nvidia.dali._autograph.converters import return_statements
  from nvidia.dali._autograph.core import converter_testing
label_desc: Use image node_id 17 for calling the SingleReturnTest obj's underlying member method code with example usage: obj.test_while_loop() and returns: unknown, s