Practice sorting lists for my Computer Science class

list_sort.py

import random, time

### Test case functions
# Check for sorted list
def is_sorted(a:list) -> bool:
    for i in range(len(a) - 1):
        if a[i] > a[i + 1]:
            return False
    return True

# Test if sort function works
def test_sort(func:callable, size:int, max_size:int) -> None:
    print('Testing sort %s()...' % func.__name__)
    test_list = []
    for i in range(size):
        test_list.append(random.randint(0, max_size))
    #print('Random list generated:\n%s' % test_list)
    test_start = time.time()
    func(test_list)
    print('Sort took %s seconds.' % (time.time() - test_start))
    #print('List after sort:\n%s' % test_list)
    print('%s %s.' % (func.__name__, 'works' if is_sorted(test_list) else 'does NOT work'))

### Sort functions
def swap(a:list, i:int, j:int) -> None:
    a[i], a[j] = a[j], a[i]

# Merge sort
def merge_sort(a:list) -> None:
    b = a[:len(a)//2]
    c = a[len(a)//2:] # when a is odd, always bigger
    if len(b) > 1:
        merge_sort(b)
        merge_sort(c)
    elif len(c) > 1:
        merge_sort(c)
    a.clear()
    while len(b) > 0 or len(c) > 0:
        if len(b) == 0:
            a.append(c.pop(0))
        elif len(c) == 0:
            a.append(b.pop(0))
        else:
            if b[0] > c[0]:
                a.append(c.pop(0))
            else:
                a.append(b.pop(0))

def bubble_sort(a:list) -> None:
    for i in range(len(a)):
        for j in range(len(a) - i - 1):
            if a[j] > a[j + 1]:
                swap(a, j + 1, j)

### Python functions
def main() -> None:
    size = int(input('What size?\n> '))
    max_size = int(input('Max int size?\n> '))

    # Test cases
    test_sort(merge_sort, size, max_size)
    test_sort(bubble_sort, size, max_size)

if __name__ == '__main__':
    main()