keras如何将我的模型的输出提供给输入变量

from tensorflow import keras
from tensorflow.keras import layers

inputs = keras.Input(shape=(input_shape,))
x = layers.Dense(units=64, activation='relu')(inputs)
# 添加其他层

outputs = layers.Dense(units=output_shape, activation='softmax')(x)

model = keras.Model(inputs=inputs, outputs=outputs)

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

model.fit(x_train, y_train, batch_size=batch_size, epochs=epochs, validation_data=(x_val, y_val))

predictions = model.predict(x_test)