import random
import string


def get_random_num_code(length=8):
    return "".join(random.choices(string.digits, k=length))


def get_random_letter_code(length=8):
    return "".join(random.choices(string.ascii_lowercase, k=length))


def get_random_letter_and_num_code(length=4):
    return ''.join(random.sample(string.ascii_letters + string.digits, 4))