old_contents: import sys
  import gc
  import os.path
  sys.path.insert(0, os.path.join(os.path.dirname(os.path.abspath(__file__)),
                                  '..', '..', 'build', 'default', 'examples', 'c-hello'))
  import hello
  import unittest
  
  
  class TestHello(unittest.TestCase):
  
      def test_func(self):
          x = hello.sum(1, 2)
          self.assertEqual(x, 3)
  
      def test_foo(self):
          foo = hello.Foo()
          data = foo.get_data()
          self.assertEqual(data, '')
          del foo
          while gc.collect():
              pass
  
  
  if __name__ == '__main__':
      unittest.main()
  
new_contents: import sys
  import gc
  import os.path
  sys.path.insert(0, os.path.join(os.path.dirname(os.path.abspath(__file__)),
                                  '..', '..', 'build', 'default', 'examples', 'c-hello'))
  import hello
  import unittest
  
  
  class TestHello(unittest.TestCase):
  
      def test_func(self):
          x = hello.sum(1, 2)
          self.assertEqual(x, 3)
  
      def test_foo(self):
          foo = hello.Foo()
          data = foo.get_data()
          self.assertEqual(data, None)
          del foo
          while gc.collect():
              pass
  
      def test_foo2(self):
          foo = hello.Foo("123")
          data = foo.get_data()
          self.assertEqual(data, "123")
          del foo
          while gc.collect():
              pass
  
      def test_foo3(self):
          foo = hello.Foo(3)
          data = foo.get_data()
          self.assertEqual(data, "   ")
          del foo
          while gc.collect():
              pass
  
  
  if __name__ == '__main__':
      unittest.main()
  
subject: fix the unit tests