title: Persist variable changes between tests in unittest?
body: <p>How do I persist changes made within the same object inheriting from <code>TestCase</code> in unitttest?</p>
  
  <pre><code>from unittest import TestCase, main as unittest_main
  
  
  class TestSimpleFoo(TestCase):
      foo = 'bar'
  
      def setUp(self):
          pass
  
      def test_a(self):
          self.assertEqual(self.foo, 'bar')
          self.foo = 'can'
  
      def test_f(self):
          self.assertEqual(self.foo, 'can')
  
  
  if __name__ == '__main__':
      unittest_main()
  </code></pre>
  
  <p>I.e.: I want those two tests above to pass</p>