original_string: protected function _createBoundary()
      {
          if ($this->_attachments || $this->_emailFormat === 'both') {
              $this->_boundary = md5(Security::randomBytes(16));
          }
      }
code: protected function _createBoundary()
      {
          if ($this->_attachments || $this->_emailFormat === 'both') {
              $this->_boundary = md5(Security::randomBytes(16));
          }
      }
code_tokens: protected function _createBoundary ( ) { if ( $ this -> _attachments || $ this -> _emailFormat === 'both' ) { $ this -> _boundary = md5 ( Security :: randomBytes ( 16 ) ) ; } }
docstring: Create unique boundary identifier
  
  @return void
docstring_tokens: Create unique boundary identifier