class CertController {
    @Value("${sonic.sgm}")
    private String version;

    @RequestMapping("/assets/download")
    public String download(Model model) {<FILL_FUNCTION_BODY>}
}

        model.addAttribute("msg", "欢迎来到证书下载页面");
        model.addAttribute("pemMsg", "👉 点击下载pem证书");
        model.addAttribute("pemName", "sonic-go-mitmproxy-ca-cert.pem");
        model.addAttribute("pemUrl", "/download/sonic-go-mitmproxy-ca-cert.pem");
        model.addAttribute("tips", "如果pem证书无效，请尝试cer证书");
        model.addAttribute("cerMsg", "👉 点击下载cer证书");
        model.addAttribute("cerName", "sonic-go-mitmproxy-ca-cert.cer");
        model.addAttribute("cerUrl", "/download/sonic-go-mitmproxy-ca-cert.cer");
        model.addAttribute("version", "Version: " + version);
        return "download";
    
<no_super_class>