public function getSchedules($page = 0, $per_page = 30)
    {
        $url = "projects/{$this->project_id}/schedules";
        $this->setJsonHeaders();
        $params = array(
            'page'     => $page,
            'per_page' => $per_page,
        );
        $schedules = self::json_decode($this->apiCall(self::GET, $url, $params));
        return $schedules->schedules;
    }