public function setHeader()
    {
        $args = func_get_args();

        if (is_array($args[0])) {
            foreach ($args[0] as $key => $value)
                $this->headers['headers'][$key] = $value;
        } else {
            $this->headers['headers'][$args[0]] = $args[1];
        }

        return $this;
    }