I installed tymon/jwt-auth and added "implements JWTSubject" on user class now I am getting error

/**

     * Get the identifier that will be stored in the subject claim of the JWT.

     *

     * @return mixed

     */

    public function getJWTIdentifier()

    {

        return $this->getKey();

    }



    /**

     * Return a key value array, containing any custom claims to be added to the JWT.

     *

     * @return array

     */

    public function getJWTCustomClaims()

    {

        return [];

    }