How to use the nmslib.knnQuery function in nmslib

query_time_param = ['efSearch=50']

    nmslib.createIndex(index, index_param)

    print('The index is created')

    nmslib.setQueryTimeParams(index,query_time_param)

    print('Query time parameters are set')

    print("Results for the freshly created index:")

    k = 3

    for idx, data in enumerate(read_data_as_string('sample_queryset.txt')):
        print(idx, nmslib.knnQuery(index, k, data))

    nmslib.saveIndex(index, index_name)

    print("The index %s is saved" % index_name)

    nmslib.freeIndex(index)

query_time_param = ['efSearch=50']


    nmslib.loadIndex(index, index_name)

    print("The index %s is loaded" % index_name)

    nmslib.setQueryTimeParams(index, query_time_param)

    print('Query time parameters are set')

    print("Results for the loaded index:")

    k = 2
    for idx, data in enumerate(QUERY_STRS):
        print(idx, nmslib.knnQuery(index, k, data))

    nmslib.freeIndex(index)

print("Results for the freshly created index:")

    with TimeIt('knn query'):
        if batch:
            num_threads = 10
            res = nmslib.knnQueryBatch(index, num_threads, k, query_matrix)
            for idx, v in enumerate(res):
                if idx < 5:
                    print(idx, v)
                if idx == 0:
                    for i in v:
                        print('q0', i, distance.cosine(q0, dataset[i,:]))
        else:
            for idx, data in enumerate(q):
                res = nmslib.knnQuery(index, k, data)
                if idx < 5:
                    print(idx, res)

    nmslib.saveIndex(index, index_name)

    print("The index %s is saved" % index_name)

    nmslib.freeIndex(index)

index_param = ['NN=17', 'efConstruction=50', 'indexThreadQty=4']
    query_time_param = ['efSearch=50']

    nmslib.createIndex(index, index_param)
    nmslib.setQueryTimeParams(index, query_time_param)

    print('Query time parameters are set')

    print("Results for the freshly created index:")

    k = 2
    if batch:
        num_threads = 10
        res = nmslib.knnQueryBatch(index, num_threads, k, QUERY_STRS)
    for idx, data in enumerate(QUERY_STRS):
        res = nmslib.knnQuery(index, k, data)
        print(idx, data, res, [DATA_STRS[i] for i in res])

    nmslib.saveIndex(index, index_name)

    print("The index %s is saved" % index_name)

    nmslib.freeIndex(index)

print('Query time parameters are set')

    print("Results for the freshly created index:")

    k = 3

    start = time.time()
    if fast:
        num_threads = 10
        query = read_data_fast('sample_queryset.txt')
        res = nmslib.knnQueryBatch(index, num_threads, k, query)
        for idx, v in enumerate(res):
            print(idx, v)
    else:
        for idx, data in enumerate(read_data('sample_queryset.txt')):
            print(idx, nmslib.knnQuery(index, k, data))
    end = time.time()
    print('querying done in %s secs' % (end - start))

    nmslib.saveIndex(index, index_name)

    print("The index %s is saved" % index_name)

    nmslib.freeIndex(index)

def query(self, v, n):
        return nmslib.knnQuery(self._index, n, v.tolist())