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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 replace_orig_field(self, option):
 """ Replaces each original field in `option` that is registered for translation by its translation fields. Returns a new list with replaced fields. If `option` contains no registered fields, it is returned unmodified. ['title',] ['title_de', 'title_en'] ['title_de', 'title_en', 'url'] Note that grouped fields are flattened. We do this because: 1. They are hard to handle in the jquery-ui tabs implementation 2. They don't scale well with more than a few languages 3. It's better than not handling them at all (okay that's weak) ['title_de', 'title_en', 'url_de', 'url_en', 'email_de', 'email_en', 'text'] """

        if option:
            option_new = list(option)
            for opt in option:
                if opt in self.trans_opts.fields:
                    index = option_new.index(opt)
                    option_new[index:index + 1] = get_translation_fields(opt)
                elif isinstance(opt, (tuple, list)) and (
                        [o for o in opt if o in self.trans_opts.fields]):
                    index = option_new.index(opt)
                    option_new[index:index + 1] = self.replace_orig_field(opt)
            option = option_new
        return option