original_string: public function update_visibility($visible = null) {
          if (is_bool($visible)) {
              $this->_visible = $visible;
          } else {
              $this->_visible = !$this->_visible;
          }
          return $this->update_visible();
      }
code: public function update_visibility($visible = null) {
          if (is_bool($visible)) {
              $this->_visible = $visible;
          } else {
              $this->_visible = !$this->_visible;
          }
          return $this->update_visible();
      }
code_tokens: public function update_visibility ( $ visible = null ) { if ( is_bool ( $ visible ) ) { $ this -> _visible = $ visible ; } else { $ this -> _visible = ! $ this -> _visible ; } return $ this -> update_visible ( ) ; }
docstring: 1. Change visibility to the value chosen
  2. Update the type
  
  @param bool $visible
  @return bool
docstring_tokens: 1 . Change visibility to the value chosen 2 . Update the type