def pivot_left(tf):
    init()
    gpio.output(13, True)
    gpio.output(15, False)
    gpio.output(7, True)
    gpio.output(11, False)
    time.sleep(tf)
    gpio.cleanup()
    

def pivot_right(tf):
    init()
    gpio.output(13, False)
    gpio.output(15, True)
    gpio.output(7, False)
    gpio.output(11, True)
    time.sleep(tf)
    gpio.cleanup()
		

Here, we're just adding a couple pivot functions. I've just included these for quick reference, feel free to copy and paste them into your main script.