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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 _fetch_router_chunk_data(self, router_ids=None):
 """Fetch router data from the routing plugin in chunks. :param router_ids: List of router_ids of routers to fetch :return: List of router dicts of format: """


        curr_router = []
        if len(router_ids) > self.sync_routers_chunk_size:
            # fetch routers by chunks to reduce the load on server and
            # to start router processing earlier
            for i in range(0, len(router_ids),
                           self.sync_routers_chunk_size):
                routers = self.plugin_rpc.get_routers(
                                self.context, (router_ids[i:i +
                                               self.sync_routers_chunk_size]))
                LOG.debug('Processing :%r', routers)
                for r in routers:
                    curr_router.append(r)
        else:
            curr_router = self.plugin_rpc.get_routers(
                self.context, router_ids=router_ids)
        return curr_router