Generator function as a Freestyle predicate

predicate.py

def pyVertexNatureUP0D(nature):
    """ Generator function as predicate. about 50% slower, but it works """
    while True:
        print("doing work")
        inter = yield
        if inter is None:
            continue
        yield bool(inter.object.nature & nature)
        
    it = Interface0DIterator(stroke)
    next(self.pred)
    for svert, _ in zip(it, self.pred):
        c = float(self.pred.send(it))
        svert.attribute.color = (c, c, c)