laravel login through API using token

I'm using laravel 5.4 to develop an api

When trying to login using API Controller

Route::post('/login','Auth\ApiLoginController@login')

class ApiLoginController extends Controller
{
    public function login(Request $request)
    {
        $this->validate($request,[
            'email' => 'required|email',
            'password' => 'required|min:6',
        ]);

        /*return response([
            'email' =>$request->email,
            'password'=> $request->password
        ],200);*/

        if(Auth::guard('api')->attempt(['email'=> $request->email, 'password'=> $request->password], $request->remember)){
            //return redirect()->intended(route('admin.dashboard'));
                return response([
                'data' =>"login successfully"
            ], 200);
        }    

        //return redirect()->back()->withInput($request->only('email','remember'));
            return response([
            'data' =>"login failed"
        ],200);
    } 
}

It gives me following error:

{FatalThrowableError Call to undefined method Illuminate\Auth\TokenGuard::attempt()}