Monty Python on Friday (part III)

count = 0
count_max = 0
first_index_max = 0
last_index_max = 0
with open('input.txt') as f:
    text = f.read()
    l = [x for x in text]
    for i in range(len(text)):
        if text[i] == '(':
            count += 1
        if text[i] == ')':
            if count > 0:
                count -= 1
        if count_max < count:
            count_max = count
            first_index_max = i
        if count_max - 1 == count:
            last_index_max = i

    print(*text)
    print("Максимальное колчество открытых скобок: ", count_max)
    print(text[first_index_max+1:last_index_max])