import random
from typing import Iterable


def random_port(excludes: Iterable[int] = None) -> int:
    return random.choice(list(set(range(10000, 20000)) - set(excludes or [])))


def random_channel(excludes: Iterable[int] = None) -> int:
    excludes = set(list(excludes or []))
    while True:
        _channel = random.randint(1000, (1 << 31) - 1)
        if _channel not in excludes:
            return _channel