def _compressbits(bitvector, wordsize=32):
    """Compress binary vector into vector of long ints.

    This function is used by the Fingerprint class.

    >>> _compressbits([0, 1, 0, 0, 0, 1], 2)
    [2, 0, 2]
    """
    ans = []
    for start in range(0, len(bitvector), wordsize):
        compressed = 0
        for i in range(wordsize):
            if i + start < len(bitvector) and bitvector[i + start]:
                compressed += 2 ** i
        ans.append(compressed)
    return ans
