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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 _init(self):
 """ Convert model metadata to class attributes. This function is called automatically after ``define()`` in new versions. :return: None """

        assert self._name
        assert self._group

        # self.n = 0
        self.u = []
        self.name = []
        self.idx = []
        self.uid = {}

        if not self._unamey:
            self._unamey = self._algebs
        else:
            assert len(self._unamey) == len(self._algebs)

        if not self._unamex:
            self._unamex = self._states
        else:
            assert len(self._unamex) == len(self._states)

        for item in self._data.keys():
            self.__dict__[item] = []

        for bus in self._ac.keys():
            for var in self._ac[bus]:
                self.__dict__[var] = []
        for node in self._dc.keys():
            for var in self._dc[node]:
                self.__dict__[var] = []

        for var in self._states + self._algebs + self._service:
            self.__dict__[var] = []

        self._flags['sysbase'] = False
        self._flags['allocate'] = False
        self._flags['address'] = False