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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 run_loop(leds=all_leds):
 """ Start the loop. :param `leds`: Which LEDs to light up upon switch press. :type `leds`: sequence of LED objects """

    print('Loop started.\nPress Ctrl+C to break out of the loop.')
    while 1:
        try:
            if switch():
                [led.on() for led in leds]
            else:
                [led.off() for led in leds]
        except OSError: # VCPInterrupt # Ctrl+C in interpreter mode.
            break