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: remappings.rs
    path of file: ./repos/ethers-rs/ethers-solc/src
    
    the code of the file until where you have to start completion: use crate::utils;

use serde::{Deserialize, Serialize};
use std::{
    collections::{hash_map::Entry, HashMap},
    fmt,
    path::{Path, PathBuf},
    str::FromStr,
};

const DAPPTOOLS_CONTRACTS_DIR: &str = "src";
const DAPPTOOLS_LIB_DIR: &str = "lib";
const JS_CONTRACTS_DIR: &str = "contracts";
const JS_LIB_DIR: &str = "node_modules";

/// T
    
    fn relative_remapping() {
        let remapping = "oz=a/b/c/d";
        let remapping = Remapping::from_str(remapping).unwrap();

        let relative = RelativeRemapping::new(remapping.clone(), "a/b/c");
        assert_eq!(relative.path.relative(), Path::new(&remapping.path));
        assert_eq!(relative.path.original(), Path::new("d"));

        let relative = RelativeRemapping::new(remapping.clone(), "x/y");
        assert_eq!(relative.path.relative(), Path::new("x/y/a/b/c/d"));
        assert_eq!(relative.path.original(), Path::new(&remapping.path));

        let remapping = "oz=/a/b/c/d";
        let remapping = Remapping::from_str(remapping).unwrap();
        let relative = RelativeRemapping::new(remapping.clone(), "a/b");
        assert_eq!(relative.path.relative(), Path::new(&remapping.path));
        assert_eq!(relative.path.original(), Path::new(&remapping.path));
        assert!(relative.path.parent.is_none());

        let relative = RelativeRemapping::new(remapping, "/a/b");
        assert_eq!(relative.to_relative_remapping(), Remapping::from_str("oz/=c/d/").unwrap());
    }