def unique_id_for_user(user, save=True):
    """
    Return a unique id for a user, suitable for inserting into
    e.g. personalized survey links.

    Keyword arguments:
    save -- Whether the id should be saved in an AnonymousUserId object.
    """
    # Setting course_id to '' makes it not affect the generated hash,
    # and thus produce the old per-student anonymous id
    return anonymous_id_for_user(user, None, save=save)