from time import sleep
import _thread
from machine import Pin
sleep(0.1) # Wait for USB to become ready

# Core thread 0
def core0_thread():
    counter = 0
    while True:
        print(counter)
        counter += 2
        sleep(1)

def core1_thread():
    counter = 0
    while True:
        print(counter)
        counter += 2
        sleep(1)


second_thread = _thread.start_new_thread(core1_thread, ())

core0_thread()