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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_interp_indt(self, indt=None):
 """ Set the indices of the times for which to interpolate data The index can be provided as: - A 1d np.ndarray of boolean or int indices => interpolate data at these times for all channels - A dict with: * keys = int indices of channels * values = array of int indices of times at which to interpolate Time indices refer to self.ddataRef['t'] Channel indices refer to self.ddataRef['X'] """

        lC = [indt is None, type(indt) in [np.ndarray,list], type(indt) is dict]
        assert any(lC)
        if lC[2]:
            lc = [type(k) is int and k<self._ddataRef['nch'] for k in indt.keys()]
            assert all(lc)
            for k in indt.keys():
                assert hasattr(indt[k],'__iter__')
                indt[k] = _format_ind(indt[k], n=self._ddataRef['nt'])
        elif lC[1]:
            indt = np.asarray(indt)
            assert indt.ndim==1
            indt = _format_ind(indt, n=self._ddataRef['nt'])
        self._dtreat['interp-indt'] = indt
        self._ddata['uptodate'] = False