def parse(self, *args, **kwargs):
        """
        Return a list of language tags sorted by their "q" values.  For example,
        "en-us,en;q=0.5" should return ``["en-us", "en"]``.  If there is no
        ``Accept-Language`` header present, default to ``[]``.
        """
        header = self.__call__(*args, **kwargs)
        if header is None:
            return []
        langs = [v for v in header.split(",") if v]
        qs = []
        for lang in langs:
            pieces = lang.split(";")
            lang, params = pieces[0].strip().lower(), pieces[1:]
            q = 1
            for param in params:
                if param not in '=':
                    # Malformed request; probably a bot, we'll ignore
                    continue
                lvalue, rvalue = param.split("=")
                lvalue = lvalue.strip().lower()
                rvalue = rvalue.strip()
                if lvalue == "q":
                    q = float(rvalue)
            qs.append((lang, q))
        qs.sort(key=lambda query: query[1], reverse=True)
        return [lang for (lang, q) in qs]
dataset/ETHPy150Open cloudera/hue/desktop/core/ext-py/Paste-2.0.1/paste/httpheaders.py/_AcceptLanguage.parse/swapped operands of `not in`