def test_none_2(self):
self.assertIsNone(first_dup('bar'))
def test_equals_6(self):
self.assertEqual(first_dup('1a2b3a3c'), 'a')
def test_none(self):
self.assertIsNone(first_dup('like'))
def test_equals_5(self):
self.assertEqual(first_dup('!@#$!@#$'), '!')
def test_equals_4(self):
self.assertEqual(first_dup('123123'), '1')
def test_equals_3(self):
self.assertEqual(first_dup('ode to joy'), 'o')
def test_equals_2(self):
self.assertEqual(first_dup('Ode to Joy'), ' ')
def test_equals(self):
self.assertEqual(first_dup('tweet'), 't')