8 channel relay

can any body pls help with the testing of 8 channel relay ports testing individually how to turn on one by one which one we need.

pls help me with python coding for the 8 channel relay through raspberry pi3.

#!/usr/bin/python
import RPi.GPIO as GPIO
import time

GPIO.setmode(GPIO.BCM)

init list with pin numbers

pinList = [2, 3, 4, 17, 27, 22, 10, 9]

loop through pins and set mode and state to ‘low’

for i in pinList:
GPIO.setup(i, GPIO.OUT)
GPIO.output(i, GPIO.HIGH)

time to sleep between operations in the main loop

SleepTimeL = 0.2

main loop

try:
while True:

for i in pinList:
GPIO.output(i, GPIO.HIGH)
time.sleep(SleepTimeL);

pinList.reverse()

for i in pinList:
GPIO.output(i, GPIO.LOW)
time.sleep(SleepTimeL);

pinList.reverse()

End program cleanly with keyboard

except KeyboardInterrupt:
print " Quit"