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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 _add_message_info_multiple(self, msg_info):
 """ add a message info multiple to self._msg_info_multiple_dict """

        if msg_info.key in self._msg_info_multiple_dict:
            if msg_info.is_continued:
                self._msg_info_multiple_dict[msg_info.key][-1].append(msg_info.value)
            else:
                self._msg_info_multiple_dict[msg_info.key].append([msg_info.value])
        else:
            self._msg_info_multiple_dict[msg_info.key] = [[msg_info.value]]