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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 placeholder_plugin_filter(self, request, queryset):
 """ This is only used on models which use placeholders from the django-cms """

        if not request:
            return queryset
        if GLL.is_active:
            return queryset.filter(language=GLL.language_code)
        return queryset