Populating a list/array by index in Python?

Question

Is this possible:

myList = []

myList[12] = \'a\'
myList[22] = \'b\'
myList[32] = \'c\'
myList[42] = \'d\'

When I try, I get:

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Answer 1

If you don't know the size of the list ahead of time, you could use try/except and then Extend the list in the except:

L = []
def add(i, s):
    try:
        L[i] = s
    except IndexError:
        L.extend([None]*(i-len(L)+1))
        L[i] = s

add(12, 'a')
add(22, 'b')

----- Update ---------------------------------------------
Per tgray's comment: If it is likely that your code will throw an Exception most of the time, you should check the length of the List every time, and avoid the Exceptions:

L = []
def add(i, s):
    size = len(L)
    if i >= size:
        L.extend([None]*(i-size+1))
        L[i] = s