text: #!/usr/bin/env python
  import RPi.GPIO as GPIO
  import time
  
  colors = [0xFF0000, 0x00FF00, 0x0000FF, 0xFFFF00, 0xFF00FF, 0x00FFFF]
  R = 11
  G = 12
  B = 13
  
  def setup(Rpin, Gpin, Bpin):
  	global pins
  	global p_R, p_G, p_B
  	pins = {'pin_R': Rpin, 'pin_G': Gpin, 'pin_B': Bpin}
  	GPIO.setmode(GPIO.BOARD)       # Numbers GPIOs by physical location
  	for i in pins:
  		GPIO.setup(pins[i], GPIO.OUT)   # Set pins' mode is output
  		GPIO.output(pins[i], GPIO.HIGH) # Set pins to high(+3.3V) to off led
  	
  	p_R = GPIO.PWM(pins['pin_R'], 2000)  # set Frequece to 2KHz
  	p_G = GPIO.PWM(pins['pin_G'], 1999)
  	p_B = GPIO.PWM(pins['pin_B'], 5000)
  	
  	p_R.start(100)      # Initial duty Cycle = 0(leds off)
  	p_G.start(100)
  	p_B.start(100)
  
  def map(x, in_min, in_max, out_min, out_max):
  	return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min
  
  def off():
  	for i in pins:
  		GPIO.output(pins[i], GPIO.HIGH)    # Turn off all leds
  
  def setColor(col):   # For example : col = 0x112233
  	R_val = (col & 0xff0000) >> 16
  	G_val = (col & 0x00ff00) >> 8
  	B_val = (col & 0x0000ff) >> 0
  
  	R_val = map(R_val, 0, 255, 0, 100)
  	G_val = map(G_val, 0, 255, 0, 100)
  	B_val = map(B_val, 0, 255, 0, 100)
  	
  	p_R.ChangeDutyCycle(100-R_val)     # Change duty cycle
  	p_G.ChangeDutyCycle(100-G_val)
  	p_B.ChangeDutyCycle(100-B_val)
  
  def loop():
  	while True:
  		for col in colors:
  			setColor(col)
  			time.sleep(1)
  
  def destroy():
  	p_R.stop()
  	p_G.stop()
  	p_B.stop()
  	off()
  	GPIO.cleanup()
  
  if __name__ == "__main__":
  	try:
  		setup(R, G, B)
  		loop()
  	except KeyboardInterrupt:
  		destroy()
  