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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_from_request(request):
 """Return the most obvious language according the request."""

    language = request.GET.get('language', None)
    if language:
        return language

    if hasattr(request, 'LANGUAGE_CODE'):
        lang = settings.PAGE_LANGUAGE_MAPPING(str(request.LANGUAGE_CODE))
        if lang not in LANGUAGE_KEYS:
            return settings.PAGE_DEFAULT_LANGUAGE
        else:
            return lang
    else:
        return settings.PAGE_DEFAULT_LANGUAGE