def test_simple_letters(self): self.assertEqual(count_letter("a"), {"a":1}) self.assertEqual(count_letter("aa"), {"a":2})
def test_distinct_letters(self): self.assertEqual(count_letter("ab"), {"a":1, "b":1})
def test_if_exists(self): self.assertEqual(count_letter(""), {})
def test_differernt_letters(self): self.assertEqual(count_letter("b"), {"b":1})