async def test_update_f_expression(self):
    obj0 = (await IntFields.create(intnum=2147483647))
    (await IntFields.filter(id=obj0.id).update(intnum=(F('intnum') - 1)))
    obj = (await IntFields.get(id=obj0.id))
    self.assertEqual(obj.intnum, 2147483646)
async def test_update_f_expression(self):
    obj0 = (await IntFields.create(intnum=2147483647))
    (await IntFields.filter(id=obj0.id).update(intnum=(F('intnum') - 1)))
    obj = (await IntFields.get(id=obj0.id))
    self.assertEqual(obj.intnum, 2147483646)