Insertion sort algorithm in Python

insertion_sort.py

def insertion_sort(list):
    """
    Insertion sort algorithm by @luckylittle
    """

    for i in range(1, len(list)):
        current = list[i]
        while (i > 0) and (list[i-1] > current):        
            list[i] = list[i - 1]
            i -= 1
            list[i] = current
    return list

test = [2, 5, 7, 1, 6, 9, 8] # Length = 7
#       ^  ^  ^  ^  ^  ^  ^
#       0  1  2  3  4  5  6

print(insertion_sort(test))
# 1st pass = [2, 5, 1, 7, 6, 9, 8]
# 2nd pass = [2, 1, 5, 7, 6, 9, 8]
# 3rd pass = [1, 2, 5, 7, 6, 9, 8]
# 4th pass = [1, 2, 5, 6, 7, 9, 8]
# 5th pass = [1, 2, 5, 6, 7, 8, 9]

# How does it work exactly?

# First pass
# [2, 5, 7, 1, 6, 9, 8]
#  ^  ^  ^  ^  ^  ^  ^
#  0  1  2 <3  4  5  6
# i=1 , current=5
# i=2 , current=7
# i=3 , current=1
# i=3 , list[3]=1
# i=3 , list[2]=7
# i=2
# i=2 , list[2]=1
# [2, 5, 1, 7, 6, 9, 8]
#  ^  ^  ^  ^  ^  ^  ^
#  0  1  2  3  4  5  6

# Second pass
# [2, 5, 1, 7, 6, 9, 8]
#  ^  ^  ^  ^  ^  ^  ^
#  0  1 <2  3  4  5  6
# i=2 , list[2]=1
# i=2 , list[1]=5
# i=1
# i=1 , list[1]=1
# [2, 1, 5, 7, 6, 9, 8]
#  ^  ^  ^  ^  ^  ^  ^
#  0  1  2  3  4  5  6

# Third pass
# [2, 1, 5, 7, 6, 9, 8]
#  ^  ^  ^  ^  ^  ^  ^
#  0 <1  2  3  4  5  6
# i=1 , list[1]=1
# i=1 , list[0]=2
# i=0
# i=0 , list[0]=1
# [1, 2, 5, 7, 6, 9, 8]
#  ^  ^  ^  ^  ^  ^  ^
#  0  1  2  3  4  5  6

# Fourth pass
# [1, 2, 5, 7, 6, 9, 8]
#  ^  ^  ^  ^  ^  ^  ^
#  0  1  2  3 <4  5  6
# i=4 , current=6
# i=4 , list[4]=6
# i=4 , list[3]=7
# i=3
# i=3 , list[3]=6
# [1, 2, 5, 6, 7, 9, 8]
#  ^  ^  ^  ^  ^  ^  ^
#  0  1  2  3  4  5  6

# Fifth pass
# [1, 2, 5, 6, 7, 9, 8]
#  ^  ^  ^  ^  ^  ^  ^
#  0  1  2  3  4  5 <6
# i=5 , current=9
# i=6 , current=8
# i=6 , list[6]=8
# i=6 , list[5]=9
# i=5
# i=5 , list[5]=8
# [1, 2, 5, 6, 7, 8, 9]
#  ^  ^  ^  ^  ^  ^  ^
#  0  1  2  3  4  5  6