async def METHOD_NAME(c, s, a, b):
    aa = CommunicatingStream(a)
    bb = CommunicatingStream(b)
    xs = c.map(inc, range(10), workers=a.address)
    ys = c.map(dec, range(10), workers=b.address)
    adds = c.map(add, xs, ys, workers=a.address)
    subs = c.map(sub, xs, ys, workers=b.address)
    await wait([adds, subs])
    aa.update()
    bb.update()
    assert len(first(aa.transfer_outgoing.data.values())) and len(
        first(bb.transfer_outgoing.data.values())
    )
    assert len(first(aa.transfer_incoming.data.values())) and len(
        first(bb.transfer_incoming.data.values())
    )