unbelievable result

gistfile1.py

#
# Write partition to return a new array with 
# all values less then `v` to the left 
# and all values greater then `v` to the right
#
someList = [4, 5,1, 3, 0, 9, 8, 12]
def partition(L, v):
    P = L
    
    # your code here
    pos = 0
    v_pos = rank(L,v)
    print v_pos
    P[v_pos-1] = v

    for item in xrange(0,len(someList)):
    
        if someList[item] < v:
            P[pos] = someList[item]
            pos += 1
        elif someList[item] > v and v_pos < len(someList):
            print item,v_pos
            P[v_pos]= someList[item]
            v_pos += 1
        
            
    print P
    return P

def rank(L, v):
    pos = 0
    for val in L:
        if val < v:
            pos += 1
    return pos


partition(someList,4)

output:
3
1 3
3 4
4 5
5 6
6 7
[4, 5, 4, 5, 5, 5, 5, 5]