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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 _alloc(self):
 """ Allocate empty memory for dae variable indices. Called in device setup phase. :return: None """

        nzeros = [0] * self.n
        for var in self._states:
            self.__dict__[var] = nzeros[:]
        for var in self._algebs:
            self.__dict__[var] = nzeros[:]