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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 update(self):
 """ This method exposes a more simple interface to the IO module Regardless of what the control instance contains, this method will transmit the queued IO commands to the IO expander Usage: plant1Control.update(bus) """

        ControlCluster.compile_instance_masks()

        IO_expander_output(
            ControlCluster.bus, self.IOexpander,
            self.bank,
            ControlCluster.master_mask[self.bank])

        if self.bank != ControlCluster.pump_bank:
            IO_expander_output(
                ControlCluster.bus, self.IOexpander,
                ControlCluster.pump_bank,
                ControlCluster.master_mask[ControlCluster.pump_bank])