The bubble sort algorithm in python

bubblesort.py

def start():
    arr = [64,34,25,12,22,11,90]#an array of numbers
    lenght = len(arr)#this gets the amount of element (items) in this array
    for i in range(lenght-1):#looping through this array
        for j in range(0, lenght-i-1):#this then loops through each sought index
            if arr[j] > arr[j+1]:
                arr[j], arr[j+1] = arr[j+1], arr[j]#these lines compare the indexes and acts accordingly (so if one element is smaller then the other then it will switch places in the list)
    print("your sorted array is: ")
    for i in range (len(arr)):
        print("%d" %arr[i])#print the sorted array 
        if i == len(arr):
            exit(0)#will exit once the array is sorted.
start()