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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 output(channel, state):
 """ Set the output state of a GPIO pin. :param channel: the channel based on the numbering system you have specified (:py:attr:`GPIO.BOARD`, :py:attr:`GPIO.BCM` or :py:attr:`GPIO.SUNXI`). :param state: can be :py:attr:`0` / :py:attr:`GPIO.LOW` / :py:attr:`False` or :py:attr:`1` / :py:attr:`GPIO.HIGH` / :py:attr:`True`. **Output to several channels:** You can output to many channels in the same call. For example: .. code:: python chan_list = [11,12] # also works with tuples GPIO.output(chan_list, GPIO.LOW) # sets all to GPIO.LOW GPIO.output(chan_list, (GPIO.HIGH, GPIO.LOW)) # sets first HIGH and second LOW """

    if isinstance(channel, list):
        for ch in channel:
            output(ch, state)
    else:
        _check_configured(channel, direction=OUT)
        pin = get_gpio_pin(_mode, channel)
        return sysfs.output(pin, state)