def luhn10_check(number):
    """Return True if the number passes the Luhn checksum algorithm."""

    sum = 0
    while number:
        r = number % 100
        number //= 100
        z = r % 10
        r = r // 10 * 2
        sum += r // 10 + r % 10 + z

    return 0 == sum % 10