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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 pivot(self, a, b, Keep=None, NullVals=None, order = None, prefix='_'):
 """ Pivot with `a` as the row axis and `b` values as the column axis. Method wraps:: tabular.spreadsheet.pivot(X, a, b, Keep) """

        [data,coloring] = spreadsheet.pivot(X=self, a=a, b=b, Keep=Keep, 
                          NullVals=NullVals, order=order, prefix=prefix)
        data = data.view(tabarray)
        data.coloring = coloring
        return data