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: mod.rs
    path of file: ./repos/webrtc/ice/src/udp_mux
    
    the code of the file until where you have to start completion: use std::collections::HashMap;
use std::io::ErrorKind;
use std::net::SocketAddr;
use std::sync::{Arc, Weak};

use async_trait::async_trait;
use tokio::sync::
    
    async fn remove_conn_by_ufrag(&self, ufrag: &str) {
        // Pion's ice implementation has both `RemoveConnByFrag` and `RemoveConn`, but since `conns`
        // is keyed on `ufrag` their implementation is equivalent.

        let removed_conn = {
            let mut conns = self.conns.lock().await;
            conns.remove(ufrag)
        };

        if let Some(conn) = removed_conn {
            let mut address_map = self.address_map.write();

            for address in conn.get_addresses() {
                address_map.remove(&address);
            }
        }
    }