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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 encode_rfc2231(s, charset=None, language=None):
 """Encode string according to RFC 2231. If neither charset nor language is given, then s is returned as-is. If charset is given but not language, the string is encoded using the empty string for language. """

    s = url_quote(s, safe='', encoding=charset or 'ascii')
    if charset is None and language is None:
        return s
    if language is None:
        language = ''
    return "%s'%s'%s" % (charset, language, s)