from machine import Pin
from time import sleep

led_pins = [Pin(15, Pin.OUT), Pin(14, Pin.OUT), Pin(13, Pin.OUT), Pin(12, Pin.OUT), Pin(11, Pin.OUT), Pin(10, Pin.OUT), Pin(9, Pin.OUT), ]

while True:
    for led in led_pins:
        led.value(1)
        sleep(1)
        led.value(0)