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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 reply(self, to_all=True):
 """ Creates a new message that is a reply to this message :param bool to_all: whether or not to replies to all the recipients instead to just the sender :return: new message :rtype: Message """

        if not self.object_id or self.__is_draft:
            raise RuntimeError("Can't reply to this message")

        if to_all:
            url = self.build_url(self._endpoints.get('create_reply_all').format(
                id=self.object_id))
        else:
            url = self.build_url(
                self._endpoints.get('create_reply').format(id=self.object_id))

        response = self.con.post(url)
        if not response:
            return None

        message = response.json()

        # Everything received from cloud must be passed as self._cloud_data_key
        return self.__class__(parent=self, **{self._cloud_data_key: message})