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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 _setDriftList(self, drift_length):
 """ set drift length list of three elements :param drift_length: input drift_length in [m], single float, or list/tuple of float numbers """

        if isinstance(drift_length, tuple) or isinstance(drift_length, list):
            if len(drift_length) == 1:
                self.dflist = drift_length * 3
            elif len(drift_length) == 2:
                self.dflist = []
                self.dflist.extend(drift_length)
                self.dflist.append(drift_length[0])
            elif len(drift_length) >= 3:
                self.dflist = drift_length[0:3]
                if self.dflist[0] != self.dflist[-1]:
                    print("warning: chicane is not symmetric.")
            else:
                print("drift_length is not a valid list or tuple.")
                self.mflag = False
        else:
            self.dflist = []
            self.dflist.extend([drift_length, drift_length, drift_length])