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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 _write_gpio(self, gpio=None):
 """Write the specified byte value to the GPIO registor. If no value specified the current buffered value will be written. """

        if gpio is not None:
            self.gpio = gpio
        self.i2c.write_list(self.GPIO, self.gpio)