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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 set_dtreat_indt(self, t=None, indt=None):
 """ Store the desired index array for the time vector If an array of indices (refering to self.ddataRef['t'] is not provided, uses self.select_t(t=t) to produce it """

        lC = [indt is not None, t is not None]
        if all(lC):
            msg = "Please provide either t or indt (or none)!"
            raise Exception(msg)

        if lC[1]:
            ind = self.select_t(t=t, out=bool)
        else:
            ind = _format_ind(indt, n=self._ddataRef['nt'])
        self._dtreat['indt'] = ind
        self._ddata['uptodate'] = False