def _get_common_ancestor_or_none(repo, left_oid, right_oid):
    try:
        return repo.merge_base(left_oid, right_oid)
    except __HOLE__:
        # Couldn't find merge base
        return None
dataset/ETHPy150Open hulu/restfulgit/restfulgit/porcelain/retrieval.py/_get_common_ancestor_or_none