original_string: public function addTab($tabId, $tab)
      {
          parent::addTab($tabId, $tab);
  
          if ($this->_tabs[$tabId] instanceof Mage_Core_Block_Abstract && $this->_tabs[$tabId]->getParentBlock() === null) {
              $this->append($this->_tabs[$tabId]);
          }
  
          return $this;
      }
code: public function addTab($tabId, $tab)
      {
          parent::addTab($tabId, $tab);
  
          if ($this->_tabs[$tabId] instanceof Mage_Core_Block_Abstract && $this->_tabs[$tabId]->getParentBlock() === null) {
              $this->append($this->_tabs[$tabId]);
          }
  
          return $this;
      }
code_tokens: public function addTab ( $ tabId , $ tab ) { parent :: addTab ( $ tabId , $ tab ) ; if ( $ this -> _tabs [ $ tabId ] instanceof Mage_Core_Block_Abstract && $ this -> _tabs [ $ tabId ] -> getParentBlock ( ) === null ) { $ this -> append ( $ this -> _tabs [ $ tabId ] ) ; } return $ this ; }
docstring: Add new tab
  
  @param   string $tabId
  @param   array|Varien_Object $tab
  @return  Mage_Adminhtml_Block_Widget_Tabs
docstring_tokens: Add new tab