How to fill a list

Question

I have to make a function that takes an empty list as first argument and n as secound argument, so that:

L=[]
function(L,5)
print L
returns:
[1,2,3,4,5]
         


        

Answer 1

A function without an explicit return or yield returns None. What you want is

def fill_list(l, n):
    for i in xrange(1, n+1):
        l.append(i)
    return l

but that's very unpythonic. You'd better just call range(1, n+1) which also returns the list [1,2,3,4,5] for n=5:

def fill_list(n):
    return range(1, n+1)