def hash_labels_only(**data):
    """
    Computes a hash value only based on a list of labels.

    :param data: Contains the keyword arguments passed in. Requires 2 keyword arguments:
    labels: A list of strings

    node_label_hash: A Dictionary of String -> integer
    Each label is assigned an integer which is a power of 2, to ensure that each combination
    of labels has a unique hash value.
    :return: An integer
    """

    labels = data["labels"]
    node_label_hash = data["node_label_hash"]

    hash_value = 0
    for label in labels:
        hash_value += node_label_hash[label]

    return hash_value