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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 remove(self, order, cells):
 """Remove cells at a given order from the MOC. """


        self._normalized = False

        order = self._validate_order(order)

        for cell in cells:
            cell = self._validate_cell(order, cell)

            self._compare_operation(order, cell, True, 'remove')