OUTPUT_A = 'outA' OUTPUT_B = 'outB' OUTPUT_C = 'outC' OUTPUT_D = 'outD' INPUT_1 = 'in1' INPUT_2 = 'in2' INPUT_3 = 'in3' INPUT_4 = 'in4' BUTTONS_FILENAME = None EVDEV_DEVICE_NAME = None LEDS = {} LED_GROUPS = {} LED_COLORS = {}