You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: last_common_header.rs
    path of file: ./repos/ckb/test/src/specs/sync
    
    the code of the file until where you have to start completion: use crate::utils::{build_compact_block, wait_until};
use crate::{Net, Node, Spec};
use ckb_network::SupportProtocols;

pub struct LastCommonHeaderForPeerWithWorseChain;

impl Spec for LastCommonHeaderForPeerWithWorseChain {
    // As for the peers of which main chain is worse than ours, we should ensure the
    // last_common_header updating as well.
    fn run(&self, nodes: &mut Vec<Node>) {
        let node0 = &nodes[0];

        // Node0's main chain tip is 5
        node0.mine(5);
        let worse = (1..=4)
            .map(|number| node0.get_block_by_number(number))
            .collect::<Vec<_>>();

        // Net relay blocks[1..4] to node0, let node0 knows our best chain is at 4.
        let mut net = Net::new(
    
    fn run(&self, nodes: &mut Vec<Node>) {
        let node0 = &nodes[0];

        // Node0's main chain tip is 5
        node0.mine(5);
        let worse = (1..=4)
            .map(|number| node0.get_block_by_number(number))
            .collect::<Vec<_>>();

        // Net relay blocks[1..4] to node0, let node0 knows our best chain is at 4.
        let mut net = Net::new(
            self.name(),
            node0.consensus(),
            vec![SupportProtocols::Sync, SupportProtocols::RelayV3],
        );
        net.connect(node0);
        for block in worse {
            net.send(
                node0,
                SupportProtocols::RelayV3,
                build_compact_block(&block),
            );
        }

        // peer.last_common_header is expect to be advanced to peer.best_known_header
        let last_common_header_synced = wait_until(10, || {
            let sync_state = node0
                .rpc_client()
                .get_peers()
                .into_iter()
                .filter(|remote_node| remote_node.node_id == net.node_id())
                .last()
                .and_then(|node| node.sync_state);
            if sync_state
                .as_ref()
                .map(|sync_state| sync_state.last_common_header_number == Some(4.into()))
                .unwrap_or(false)
            {
                return true;
            }
            false
        });
        assert!(last_common_header_synced);
    }