Python nested function return statement not working

I was working on this problem where I need to remove items from the list from left to right and then right to left till only one item remains. To solve this I was using the recursion method and I was able to get the desired values. But for some reason, the return statement won't work when the if the condition(len(addL) == 1) is True. Appreciate any help on this. Please check the code below

class Solution(object):
def lastRemaining(self, n):
    addL = []
    switch = False

    for i in xrange(1,n + 1):
        addL.append(i)


    def removeO(addL,switch):
        if len(addL) == 1:
            return addL
        if len(addL) != 1:
            if not switch:

                addL = [item for item in addL if item not in addL[::2]]
                switch = True
                removeO(addL,switch)

            if switch:

                addL = [item for item in addL if item not in addL[::-2]]
                switch = False
                removeO(addL,switch)


    final = removeO(addL,False)
    return final