def METHOD_NAME(commit_ref: str) -> List[str]:
    """
    Returns the list of all parent commits of a given commit.  Exactly one for
    usual commits, but can be any number for n-way merge commits.
    """
    try:
        res = run_git(["log", "--pretty=%P", "-n", "1", commit_ref]).split()
        return res
    except subprocess.CalledProcessError as e:
        abort(f"{METHOD_NAME.__name__} failed with error: {e}")