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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 as_column_wise_lists(self, transpose=False):
 """Generator over the columns of lists"""

        # make this a generator of generators?
        if transpose:
            ans = self.from_row_wise_lists(self.as_column_wise_lists(transpose=False))
            return ans
        #print self
        return self.values()