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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 req_rr_to_non_rtc_peers(self, route_family):
 """Makes refresh request to all peers for given address family. Skips making request to peer that have valid RTC capability. """

        assert route_family != RF_RTC_UC
        for peer in self._peers.values():
            # First check if peer is in established state
            if (peer.in_established and
                # Check if peer has valid capability for given address
                # family
                    peer.is_mbgp_cap_valid(route_family) and
                # Check if peer has valid capability for RTC
                    not peer.is_mbgp_cap_valid(RF_RTC_UC)):
                peer.request_route_refresh(route_family)