当我运行这个代码我得到错误

    import tensorflow as tf
from tensorflow import keras
import numpy as np
import matplotlib.pyplot as plt

data = keras.datasets.fashion_mnist
(train_images, train_labels), (test_images, test_labels) = data.load_data()

train_images = train_images/255.0
test_images = test_images/255.0

class_names = ['T-shirt/top', 'Trouser', 'Pullover', 'Dress', "Coat", 'Sandal', 'shirt', 'Sneaker', 'Bag', 'Ankle boot']

model = keras.Sequential([

    keras.layers.Flatten(input_shape=(28,28)),
    keras.layers.Dense(128, activation='relu'),
    keras.layers.Dense(10, activation='softmax')
    ])

model.compile(optimizer='adam', loss='sparse_categorical_crossentropy', metrics=['accuracy'])

model.fit(train_images, train_labels, epochs=5)

test_loss, test_acc = model.evaluate(test_images, test_labels)
print('Test accuracy : ', test_acc)

prediction = model.predict(test_images)

for i  in range(5):
    plt.grid(False)
    plt.imshow(test_images[i], cmap=plt.cm.binary)
    plt.xlabel("Actual : " + test_labels[i])
    plt.title("Prediction : ",class_names[np.argmax(prediction[i])])
    plt.show()

Traceback（最近的调用最后）：文件"C：/用户/dwark/PycharmProjects/test/神经网络01.py"，第33行，在plt.xlabel（"实际："test_labels[i]）TypeError：只能连接str（不是"numpy.uint8"）到str