def test_case_2(self):
expected = ["3z4", "3Z4"]
solution = l.Solution()
result = solution.letterCasePermutation(self.example2)
self.assertEqual(expected, result)
def test_case_5(self):
expected = [""]
solution = l.Solution()
result = solution.letterCasePermutation(self.example5)
self.assertEqual(expected, result)
def test_case_1(self):
expected = ["a1b2", "a1B2", "A1b2", "A1B2"]
solution = l.Solution()
result = solution.letterCasePermutation(self.example1)
self.assertEqual(expected, result)