Ответ к предыдущей задаче для новичков

# Функция, которая находит добавленную букву
def find_added_letter(s, t):
count = {}

for char in t:
if char in count:
count[char] += 1
else:
count[char] = 1

for char in s:
count[char] -= 1
if count[char] == 0:
del count[char]

return list(count.keys())[0]

# Тесты для функции find_added_letter(s, t)
def test_find_added_letter():
assert find_added_letter("abcd", "abcde") == "e"
assert find_added_letter("", "y") == "y"
assert find_added_letter("hello", "heoll") == "l"
assert find_added_letter("abc", "acb") == "b"
assert find_added_letter("xy", "xyz") == "z"

#задача #coding