raspberry pi stepper motor python not working but leds are code example

Example: raspberry pi stepper motor python code

import RPi.GPIO as GPIOimport timeGPIO.setmode(GPIO.BOARD)control_pins = [7,11,13,15]for pin in control_pins:  GPIO.setup(pin, GPIO.OUT)  GPIO.output(pin, 0)halfstep_seq = [  [1,0,0,0],  [1,1,0,0],  [0,1,0,0],  [0,1,1,0],  [0,0,1,0],  [0,0,1,1],  [0,0,0,1],  [1,0,0,1]]for i in range(512):  for halfstep in range(8):    for pin in range(4):      GPIO.output(control_pins[pin], halfstep_seq[halfstep][pin])    time.sleep(0.001)GPIO.cleanup()