upd_traffic_sig.py

def updateTrafficSignal():
	global trafficLightNormalCurrState
	state = emergencyVehicleState["state"]
	if state == NORMAL:

		if (LIGHT_RED == trafficLightNormalCurrState):
			print "Switching to RED\n"	
			set_red()
		elif (LIGHT_YELLOW == trafficLightNormalCurrState):
			print "Switching to YELLOW\n"	
			set_yellow()
		elif (LIGHT_GREEN == trafficLightNormalCurrState):
			print "Switching to GREEN\n"	
			set_green()

		time.sleep(trafficLightNormalCycleTime[trafficLightNormalCurrState])

		trafficLightNormalCurrState = trafficLightNormalCycle[ (trafficLightNormalCurrState + 1) % 3]

	elif state == CRITICAL:
		set_green()
		print "Detected Critical Distance from Emergency Vehicle\n"

		print "Switching to GREEN and Hold\n"
		time.sleep(3)