def numbits_union(numbits1: bytes, numbits2: bytes) -> bytes:
    """Compute the union of two numbits.

    Returns:
        A new numbits, the union of `numbits1` and `numbits2`.
    """
    byte_pairs = zip_longest(numbits1, numbits2, fillvalue=0)
    return bytes(b1 | b2 for b1, b2 in byte_pairs)
Compute the union of two numbits.

    Returns:
        A new numbits, the union of `numbits1` and `numbits2`.
    
coverage/numbits.py