Jetpack::admin_url PHP Method

    public static function admin_url($args = null)
    {
        $args = wp_parse_args($args, array('page' => 'jetpack'));
        $url = add_query_arg($args, admin_url('admin.php'));
        return $url;
    }

 /**
  * Authorizations
  */
 function client_authorize()
 {
     $data = stripslashes_deep($_GET);
     $data['auth_type'] = 'client';
     $role = Jetpack::translate_current_user_to_role();
     $redirect = isset($data['redirect']) ? esc_url_raw((string) $data['redirect']) : '';
     $this->check_admin_referer("jetpack-authorize_{$role}_{$redirect}");
     $result = $this->authorize($data);
     if (is_wp_error($result)) {
         Jetpack::state('error', $result->get_error_code());
     }
     if (wp_validate_redirect($redirect)) {
         $this->wp_safe_redirect($redirect);
     } else {
         $this->wp_safe_redirect(Jetpack::admin_url());
     }
     /**
      * Fires after the Jetpack client is authorized to communicate with WordPress.com.
      *
      * @since 4.2.0
      *
      * @param int Jetpack Blog ID.
      */
     do_action('jetpack_client_authorized', Jetpack_Options::get_option('id'));
     $this->do_exit();
 }