为什么我的网址访问失败

好的，所以我有一个网站，我正在制作一个python脚本，通过将其作为GET请求发送到php脚本来将数据插入网站，但是每当我放置一个没有字母或数字字符的脚本时，例如（@[];:)我收到一个 urllib 错误，指出我的 url 中没有主机：

        return urllib.urlopen("http://this-is-an-example.com/thisisadirectory/file.php?f=Hello&v="+cgi.escape("This is@A#!T33ST::::;'[]{}"))
      File "Python25'lib'urllib.py", line 82, in urlopen
        return opener.open(url)
      File "Python25'lib'urllib.py", line 190, in open
        return getattr(self, name)(url)
      File "Python25'lib'urllib.py", line 301, in open_http
        if not host: raise IOError, ('http error', 'no host given')
    IOError: [Errno http error] no host given

我还尝试制作自己的转义函数来转义所有特殊字符（或至少几个）

    full_escape_chars = {" ": "%20",
                    "<": "%3C",
                    ">": "%3E",
                    "#": "%23",
                    "'%": "%25",
                    "{": "%7B",
                    "}": "%7D",
                    "|": "%7C",
                    "''": "%5C",
                    "^": "%5E",
                    "~": "%7E",
                    "[": "%5B",
                    "]": "%5D",
                    "`": "%60",
                    ";": "%3B",
                    "/": "%2F",
                    "?": "%3F",
                    ":": "%3A",
                    "@": "%40",
                    "=": "%3D",
                    "&": "%26",
                    "$": "%24"}
    def full_escape(s):
        global full_escape_chars
        for key in full_escape_chars.keys():
            s = s.replace(key, full_escape_chars[key])
        return s

但是，仍然没有。请就如何解决此问题提出建议！提前谢谢。