Fibonacci method

def fibonacci_numbers(n):
    return 1 / (5 ** 0.5) * \
           (((1 + 5 ** 0.5) / 2) ** n
            - ((1 - 5 ** 0.5) / 2) ** n)


def steps(eps, a, b, x, y, n, k):
    if func(x) > func(y):
        a_k1 = x
        b_k1 = b
        x_k1 = y
        y_k1 = a_k1 + fibonacci_numbers(n - k - 1) * (b_k1 - a_k1) / fibonacci_numbers(n - k)
        if k != n - 2:
            k += 1
            return steps(eps, a_k1, b_k1, x_k1, y_k1, n, k + 1)
        else:
            fifth_step = "Не знаю, как сделать 5 шаг"
            return fifth_step
    else:
        a_k1 = a
        b_k1 = y
        y_k1 = x
        x_k1 = a_k1 + fibonacci_numbers(n - k - 2) * (b_k1 - a_k1) / fibonacci_numbers(n - k)
        if k != n - 2:
            return steps(eps, a_k1, b_k1, x_k1, y_k1, n, k + 1)
        else:
            fifth_step = "Не знаю, как сделать 5 шаг"
            return fifth_step

def fibonacci(eps, a0, b0):
    e = (b0 - a0) / eps
    n = 1
    while fibonacci_numbers(n) <= e:
        n += 1
    fn = fibonacci_numbers(n)
    x = a0 + fibonacci_numbers(n - 2) / fn * (b0 - a0)
    y = a0 + fibonacci_numbers(n - 1) / fn * (b0 - a0)
    print(steps(eps, a0, b0, x, y, n, 1))