Angular 2：找不到模块'./data.service angular 2

Question

尝试使用rest api时出现此错误。 找不到模块'./data.service angular 2

import { Injectable } from '@angular/core';
import { DataService } from './data.service';
import {Http} from '@angular/http';

@Injectable()
export class GithubFollowersService extends DataService{

    constructor(http: Http) {
        super('https://api.github.com/users/mosh-hamedani/followers', http);
    }

}