call to undefined method photos() laravel project flyer

I'm working on laravel's project flyer and I'm continually getting this error from artisan tinker.

 $flyer->photos()->create(['photo' => 'foo.jpg']);

BadMethodCallException with message 'Call to undefined method Illuminate \Database\Query\Builder::photos()'

Here is my Flyer.php file:

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Flyer extends Model
{
    public function photos()
    {
        return $this->hasMany('App\Photo');
    }
}

and here is my Photo.php file:

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Photo extends Model
{
    protected $table = 'flyer_photos';

    protected $fillable = ['photo'];

    public function flyer()
    {
        return $this->belongsTo('App\Flyer');
    }
}

looks like the method photos() doesn't get recognised or something

via Chebli Mohamed