from mfrc522 import MFRC522
from time import sleep

reader = MFRC522(spi_id=0, sck=18, mosi=19, miso=16, cs=17, rst=9)

while True:
    print("Place the card...")

    stat, tag_type = reader.request(reader.REQIDL)

    if stat == reader.OK:
        stat, uid = reader.anticoll()

        if stat == reader.OK:
            print("UID:", uid)

    sleep(1)