Something

function assign_block_vars($blockname, $data)
{
    $blockCode = $this->get_block($blockname);
    foreach ($data as $key => $value) {
        str_replace ("{".$blockname.".".$value."}", $value, $blockCode);
    }
    str_replace ($this->return[0], $blockCode.$this->return[0], $this->page);
}