def add_lumOff(self, value):
        lumOff = self._add_lumOff()
        lumOff.val = value
        return lumOff
Swap the two given columns of the matrix in-place.
dataset/ETHPy150Open scanny/python-pptx/pptx/oxml/dml/color.py/_BaseColorElement.add_lumOff--crossover with--dataset/ETHPy150Open sympy/sympy/sympy/matrices/dense.py/MutableDenseMatrix.col_swap