def METHOD_NAME(a, b):
    diffs = []
    for ba in a:
        found = False
        for bb in b:
            if ba.seq == bb.seq and ba.ext == bb.ext:
                found = True
                d = diffBundle(ba, bb)
                if d:
                    diffs.append(d)
                break
        if not found:
            bb = Bundle(
                    seq=ba.seq,
                    ext=ba.ext,
                    bundleName=ba.bundleName,
                    totalBytes=0,
                    files={}
            )
            d = diffBundle(ba, bb)
            if d:
                diffs.append(d)
    for bb in b:
        found = False
        for ba in a:
            if bb.seq == ba.seq and ba.ext == bb.ext:
                found = True
        if not found:
            ba = Bundle(
                    seq=bb.seq,
                    ext=bb.ext,
                    bundleName=bb.bundleName,
                    totalBytes=0,
                    files={}
            )
            d = diffBundle(ba, bb)
            if d:
                diffs.append(d)
    diffs.sort(key=lambda x: x.total.newBytes, reverse=True)
    return diffs