So I'm writing a function that is going to multiply each number at an odd index in a `list` by `2`. I'm stuck though, as I really don't know how to approach it.

This is my code.

```
def produkt(pnr):
    for i in pnr:
        if i % 2 != 0:
            i = i * 2
    return pnr

```

If I, for example, type `produkt([1,2,3])` I get `[1,2,3]` back but I would want it to be `[2,2,6]`.