```
a = [0,   -4, 4,    6, 2, 5, 8]
b = [5, None, 3, None, 3, 2, 0]
c = [5,   -4, 3,    6, 3, 2, 0]

```

I want to take `a` and `b` as inputs and get `c`, ideally using a list comprehension. Obviously I could iterate through this with a loop, but I'm wondering if there is a more elegant/pythonic solution.