Bubble sort in Python

bubblesort.py

# This is a simple implementation of bubblesort
# which I made during a Python lesson

from random import shuffle

# size of the list that will ne sorted
n = int(input('Size of the input vector: '))
l = list(range(n))

# shuffle list
shuffle(l)

print('start:', l)

changed = True  # flag to know when the list has not been changed
passes = 0  # count number of passes
changes = 0  # count number of changes to the list

# repeat until numbers don't swap positions anymore in a pass
# after a pass, if no number changes position in the list, it means the algorithm is over
while changed:
    changed = False
    passes += 1

    # iterate through the list
    for i in range(len(l) - 1):

        # if the number in the current position is larger than the number in the next position
        if l[i] > l[i + 1]:
            changes += 1

            # we swap them
            aux = l[i]
            l[i] = l[i + 1]
            l[i + 1] = aux

            # swaping two numbers means we'll need to make another pass after the current one ends
            changed = True

print('  end:', l)
print('passes:', passes)
print('changes:', changes)