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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 randomize(self):
 """Create a new motif with shuffled positions. Shuffle the positions of this motif and return a new Motif instance. Returns ------- m : Motif instance Motif instance with shuffled positions. """

        random_pfm = [[c for c in row] for row in self.pfm]
        random.shuffle(random_pfm)
        m = Motif(pfm=random_pfm)
        m.id = "random"
        return m