substituting list comprehensions for map()

[Anh Hai Trinh]

> Try turning this into a list comprehension:
>
>   vectorsum = lambda *args: map(sum, zip(*args))
>
>   vectorsum([1,2], [3,4], [5,6])
> ->[9, 12]
>   vectorsum([1,2], [3,4], [5,6], [7,8])
> ->[16, 20]

Nvm, it's actually easy:
  vectorsum = lambda *args: [sum(i) for i in zip(*args)]