def test_2ESpecialOfferGivesOneFreeB(self):
    self.assertEqual(checkout('EE'), (checkout('E') + checkout('E')))
    self.assertEqual(checkout('EEB'), (checkout('E') + checkout('E')))
    self.assertEqual(checkout('EEBEE'), (checkout('E') * 4))
    self.assertEqual(checkout('EEBEEB'), (checkout('E') * 4))
    self.assertEqual(checkout('EEBEEBB'), ((checkout('E') * 4) + checkout('B')))
def test_2ESpecialOfferGivesOneFreeB(self):
    self.assertEqual(checkout('EE'), (checkout('E') + checkout('E')))
    self.assertEqual(checkout('EEB'), (checkout('E') + checkout('E')))
    self.assertEqual(checkout('EEBEE'), (checkout('E') * 4))
    self.assertEqual(checkout('EEBEEB'), (checkout('E') * 4))
    self.assertEqual(checkout('EEBEEBB'), ((checkout('E') * 4) + checkout('B')))