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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 register_rp_hook(r, *args, **kwargs):
 """This is a requests hook to register RP automatically. You should not use this command manually, this is added automatically by the SDK. See requests documentation for details of the signature of this function. http://docs.python-requests.org/en/master/user/advanced/#event-hooks """

    if r.status_code == 409 and 'msrest' in kwargs:
        rp_name = _check_rp_not_registered_err(r)
        if rp_name:
            session = kwargs['msrest']['session']
            url_prefix = _extract_subscription_url(r.request.url)
            if not _register_rp(session, url_prefix, rp_name):
                return
            req = r.request
            # Change the 'x-ms-client-request-id' otherwise the Azure endpoint
            # just returns the same 409 payload without looking at the actual query
            if 'x-ms-client-request-id' in req.headers:
                req.headers['x-ms-client-request-id'] = str(uuid.uuid1())
            return session.send(req)