sort.py

def sort(artist_list):
    """Sorts a list of strings alphabetitcally using merge sort"""
    if len(artist_list) > 1:  # If the length of the list is greater than 1 run this
        middleIndex = len(artist_list) // 2  # Middle Index is halfway point of the list using int division
        leftList = artist_list[:middleIndex]
        rightList = artist_list[middleIndex:]  # left and right list created by splitting list by that middle index
        sort(leftList)
        sort(
            rightList)  # recursive call of the left and right list to further break down the list till it gets to
        # length 1 where it will no longer run the if statement
        indexMain = 0
        indexLeft = 0
        indexRight = 0  # creation of indexes for each list
        while indexLeft < len(leftList) and indexRight < len(
                rightList):  # Runs through the left and right list at the same time while comparing them until one
            # of the lists reaches the end
            leftString = leftList[indexLeft].lower()
            leftString = leftString.replace(" ", "")
            rightString = rightList[indexRight].lower()
            rightString = rightString.replace(" ",
                                              "")  # Right and Left string created by standarizing each string to all
            # lowercase and no spaces
            if leftString <= rightString:
                artist_list[indexMain] = leftList[indexLeft]
                indexLeft += 1  # If the leftString is alphabetically before rightString i.e. <= it will set the main
                # string at indexMain to the leftList at indexLeft
            else:
                artist_list[indexMain] = rightList[indexRight]
                indexRight += 1  # If the leftString is alphabetically after rightString i.e. <= it will set the main
                # string at indexMain to the rightList at indexRight
            indexMain += 1  # Index of main increased by 1 to go to next element
        while indexLeft < len(leftList):
            artist_list[indexMain] = leftList[indexLeft]
            indexLeft += 1
            indexMain += 1  # All remaining parts of the left list if left is greater than right at that time,
            # run through here to set remaining values of index main to leftList
        while indexRight < len(rightList):
            artist_list[indexMain] = rightList[indexRight]
            indexRight += 1
            indexMain += 1  # All remaining parts of the right list if right is greater than left at that time,
            # run through here to set remaining values of index main to rightList