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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def on_patch(resc, req, resp, rid):
 """ Deserialize the payload & update the single item """


    signals.pre_req.send(resc.model)
    signals.pre_req_update.send(resc.model)

    props = req.deserialize()
    model = find(resc.model, rid)

    from_rest(model, props)
    goldman.sess.store.update(model)

    props = to_rest_model(model, includes=req.includes)
    resp.last_modified = model.updated
    resp.serialize(props)

    signals.post_req.send(resc.model)
    signals.post_req_update.send(resc.model)