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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 get_language(self):
 """ Return a locale code we support on the site using the user's Accept-Language header to determine which is best. This mostly follows the RFCs but read bug 439568 for details. """

        if 'lang' in self.request.GET:
            lang = self.request.GET['lang'].lower()
            if lang in settings.LANGUAGE_URL_MAP:
                return settings.LANGUAGE_URL_MAP[lang]

        if self.request.META.get('HTTP_ACCEPT_LANGUAGE'):
            best = self.get_best_language(
                self.request.META['HTTP_ACCEPT_LANGUAGE'])
            if best:
                return best
        return settings.LANGUAGE_CODE