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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 transforms(self):
 """Return an array of arrays of column transforms. #The return value is an list of list, with each list being a segment of column transformations, and #each segment having one entry per column. """


        tr = []
        for c in self.columns:
            tr.append(c.expanded_transform)

        return six.moves.zip_longest(*tr)