Where should 'import' statement be put?

[Sean 'Shaleh' Perry]

> 
> I believe imports are done only once regardless of the number of times
> the statement appears, but are there any other considerations here? I
> realize there may be scoping issues as well.
> 

def foo(input):
    import a_module

    a_module.do_things


if foo is never called a_module is never imported.  So if you could place
potentially unused modules inside functions this helps.  But this is also a
matter of style.