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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def url_param2value(param):
 """ CONVERT URL QUERY PARAMETERS INTO DICT """

    if param == None:
        return Null
    if param == None:
        return Null

    def _decode(v):
        output = []
        i = 0
        while i < len(v):
            c = v[i]
            if c == "%":
                d = hex2chr(v[i + 1:i + 3])
                output.append(d)
                i += 3
            else:
                output.append(c)
                i += 1

        output = text_type("".join(output))
        try:
            return json2value(output)
        except Exception:
            pass
        return output

    query = Data()
    for p in param.split('&'):
        if not p:
            continue
        if p.find("=") == -1:
            k = p
            v = True
        else:
            k, v = p.split("=")
            v = _decode(v)

        u = query.get(k)
        if u is None:
            query[k] = v
        elif is_list(u):
            u += [v]
        else:
            query[k] = [u, v]

    return query