human
Here's a good function header given the following:
I wrote the below code

    io_loop = ioloop.IOLoop()
    io_loop.make_current()
    def _close():
        io_loop.clear_current()
        if ((not ioloop.IOLoop.initialized()) or (io_loop is not ioloop.IOLoop.instance())):
            io_loop.close(all_fds=True)
    request.addfinalizer(_close)
    return io_loop

What's a good function header?
assistant
#Here's a good function header.

@fixture(scope='module')
def io_loop(request):