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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 edit_text(self, message_id, text, markup=None, parse_mode=None):
 """ Edit the message in this chat. :param int message_id: ID of the message to edit :param str text: Text to edit the message to :param dict markup: Markup options :param str parse_mode: Text parsing mode (``"Markdown"``, ``"HTML"`` or ``None``) """

        if markup is None:
            markup = {}

        return self.bot.edit_message_text(
            self.id,
            message_id,
            text,
            reply_markup=self.bot.json_serialize(markup),
            parse_mode=parse_mode,
        )