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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 cancel_order(self, order_param):
 """Cancel an open order. Parameters order_param : str or Order The order_id or order object to cancel. """

        order_id = order_param
        if isinstance(order_param, zipline.protocol.Order):
            order_id = order_param.id

        self.blotter.cancel(order_id)