import json


def getKnnMse(path):
    """
    Retrieve knn mse score
    :param path: (str)
    :return: (float)
    """
    try:
        with open(path) as f:
            return json.load(f)['knn_mse']
    except IOError:
        print("knn_mse.json not found for {}".format(path))
        return -1