'Yields rvews matching external_id taken from source.[external_id] scope
Match is done on external_id value of repl and additional_scopes'

def find_repl(self, external_id):

    for rv in self.repl_views.values():
        if (not (rv.repl and rv.repl.is_alive())):
            continue
        rvid = rv.external_id
        additional_scopes = rv.repl.additional_scopes
        if ((rvid == external_id) or (external_id in additional_scopes)):
            (yield rv)
