def METHOD_NAME(efeature_values):
    path = "./extra_features.json"
    data = {}
    for feature_name in efeature_values:
        protocol_name, location, feature  = feature_name.split('.')
        if protocol_name not in data:
            data[protocol_name] = {}
        if location not in data[protocol_name]:
            data[protocol_name][location] = {}
        mean = efeature_values[feature_name]
        std = abs(0.2 * mean)
        data[protocol_name][location][feature] = [mean, std]
    dict_to_json(data, path)