def shuffle(self, frame=1):
        columns = range(self.getNumColumns() // frame)
        random.shuffle(columns)
        if frame > 1:
            cc = []
            for x in columns:
                cc += [x * frame + y for y in range(frame)]
            columns = cc
        self.takeColumns(columns)
shuffle multiple alignment.
dataset/ETHPy150Open CGATOxford/cgat/CGAT/Mali.py/Mali.shuffle