An implementation of the Ford-Johnson Algorithm for a 5 integer list in Python, which sorts in 7 comparisons only

sort_five_elements_seven_comparisons.py

"""As part of the 'Data Structures and Introduction to Algorithms' course, I was asked to solve the following problem:
Write a function that sorts five elements in seven comparisons in the worst case.

As I found this problem interesting, I decided to implement it in Python. For better understanding, I recommend
reading the answer from the link below, which explains the algorithm.
"""

import random
from typing import List


def sort_five_elements_in_seven_comparisons(numbers: List[int]) -> List[int]:
    """

    Based on "Ford-Johnson Algorithm" and this answer: https://stackoverflow.com/a/1935353/11808461
    """
    sublist_1 = [numbers[0], numbers[1]]
    sublist_2 = [numbers[2], numbers[3]]

    if sublist_1[0] > sublist_1[1]:
        sublist_1[0], sublist_1[1] = sublist_1[1], sublist_1[0]
    if sublist_2[0] > sublist_2[1]:
        sublist_2[0], sublist_2[1] = sublist_2[1], sublist_2[0]

    # For animation purposes, the "lower" sublist will be the one with the smallest first element out of the four.
    if sublist_1[0] < sublist_2[0]:
        sublist_1, sublist_2 = sublist_2, sublist_1

    """"
         sublist_1[0] --- sublist_1[1]
            /
           /
    <sublist_2[0]> --- sublist_2[1]
    """

    if numbers[4] > sublist_1[0]:
        if numbers[4] > sublist_1[1]:
            sublist_1.append(numbers[4])
            """
                sublist_1[0] --- sublist_1[1] --- *numbers[4]*
                   /   
                  /
            <sublist_2[0]> --- sublist_2[1]
            """
        else:
            sublist_1.insert(1, numbers[4])
            """
                sublist_1[0] --- *numbers[4]* --- sublist_1[1]
                   / 
                  /
            <sublist_2[0]> --- sublist_2[1]
            """
    else:
        if numbers[4] < sublist_2[0]:
            sublist_2.insert(0, numbers[4])
            """
                                  sublist_1[0] --- sublist_1[1]
                                     / 
                                    /
            *numbers[4]* --- <sublist_2[1]> --- sublist_2[2]
            """
        else:
            sublist_1.insert(0, numbers[4])
            """
               *numbers[4]* --- sublist_1[1] --- sublist_1[2]
                   /
                  /
            <sublist_2[0]> --- sublist_2[1]
            """

    if len(sublist_1) == 3:
        if sublist_2[1] > sublist_1[1]:
            if sublist_2[1] > sublist_1[2]:
                """ 
                    sublist_1[0] --- sublist_1[1] --- sublist_1[2] --- *sublist_2[1]*
                       / 
                      /
                <sublist_2[0]>
                """
                return [sublist_2[0], sublist_1[0], sublist_1[1], sublist_1[2], sublist_2[1]]
            else:
                """
                    sublist_1[0] --- sublist_1[1] --- *sublist_2[1]* --- sublist_1[2]
                       / 
                      /
                <sublist_2[0]>
                """
                return [sublist_2[0], sublist_1[0], sublist_1[1], sublist_2[1], sublist_1[2]]
        else:
            if sublist_2[1] < sublist_1[0]:
                """
                    *sublist_2[1]* --- sublist_1[0] --- sublist_1[1] --- sublist_1[2]
                       / 
                      /
                <sublist_2[0]>
                """
                return [sublist_2[0], sublist_2[1], sublist_1[0], sublist_1[1], sublist_1[2]]
            else:
                """
                    sublist_1[0] --- *sublist_2[1]* --- sublist_1[1] --- sublist_1[2]
                       / 
                      /
                <sublist_2[0]>
                """
                return [sublist_2[0], sublist_1[0], sublist_2[1], sublist_1[1], sublist_1[2]]
    else:
        if sublist_2[2] > sublist_1[0]:
            if sublist_2[2] > sublist_1[1]:
                """
                                    sublist_1[0] --- sublist_1[1] --- *sublist_2[2]*
                                         / 
                                        /
                <sublist_2[0]> -- sublist_2[1]
                """
                return [sublist_2[0], sublist_2[1], sublist_1[0], sublist_1[1], sublist_2[2]]
            else:
                """
                                    sublist_1[0] --- *sublist_2[2]* --- sublist_1[1]
                                         / 
                                        /
                <sublist_2[0]> -- sublist_2[1]
                """
                return [sublist_2[0], sublist_2[1], sublist_1[0], sublist_2[2], sublist_1[1]]
        else:
            if sublist_2[2] < sublist_2[1]:
                """
                                                       sublist_1[0] --- sublist_1[1]
                                                          /
                                                         /
                sublist_2[0] --- *sublist_2[2]* --- sublist_2[1] 
                """
                return [sublist_2[0], sublist_2[2], sublist_2[1], sublist_1[0], sublist_1[1]]
            else:
                """
                                                       sublist_1[0] --- sublist_1[1]
                                                          /
                                                         /
                sublist_2[0] --- sublist_2[1] --- *sublist_2[2]*  
                """
                return [sublist_2[0], sublist_2[1], sublist_2[2], sublist_1[0], sublist_1[1]]


def test_sort_five_elements_in_seven_comparisons():
    for i in range(100_000):
        random_list = [random.randint(-100, 100) for _ in range(5)]
        assert sort_five_elements_in_seven_comparisons(random_list) == sorted(random_list)

    print("All tests passed successfully.")


test_sort_five_elements_in_seven_comparisons()