code: public function set($key, $value)
      {
          if (is_array($key)) {
              foreach ($key as $k => $v) {
                  $_SESSION[$k] = $v;
              }
          } else {
              $_SESSION[$key] = $value;
          }
  
          return;
      }
docs: Set session method.
  
  @param string $key
  @param mixed  $value
  
  @return void