How to use the @truffle/require.file function in @truffle/require

async _load(options, context, deployer, resolver) {
    // Load assets and run `execute`
    const accounts = await context.interfaceAdapter.getAccounts();
    const requireOptions = {
      file: this.file,
      context: context,
      resolver: resolver,
      args: [deployer]
    };

    const fn = Require.file(requireOptions);

    const unRunnable = !fn || !fn.length || fn.length == 0;

    if (unRunnable) {
      const msg = `Migration ${
        this.file
      } invalid or does not take any parameters`;
      throw new Error(msg);
    }

    // `migrateFn` might be sync or async. We negotiate that difference in
    // `execute` through the deployer API.
    const migrateFn = fn(deployer, options.network, accounts);
    await this._deploy(options, deployer, resolver, migrateFn);
  }