我参考Keras VAE教程（https://keras.io/examples/generative/vae/）将VAE模型从Conv2D转换为Conv1D，并成功拟合了模型。
在模型拟合后，用“预测”法计算列车的平均有效损失。

x_train_pred = vae.predict(x_train)
train_mae_loss = np.mean(np.abs(x_train_pred - x_train), axis=1)

然后错误出现了

NotImplementedError                       Traceback (most recent call last)
Cell In [98], line 3
      1 # Get train MAE Loss
----> 3 x_train_pred = vae.predict(x_train)
      4 train_mae_loss = np.mean(np.abs(x_train_pred - x_train), axis=1)
      5 # train_mae_loss = np.mean(abs(x_train_pred - x_train), axis=1)

File /notebooks/users/1004831/objupyterlabgpu-1004831/kernels/mytensor2.0.0b/lib/python3.9/site-packages/keras/utils/traceback_utils.py:70, in filter_traceback.<locals>.error_handler(*args, **kwargs)
     67     filtered_tb = _process_traceback_frames(e.__traceback__)
     68     # To get the full stack trace, call:
     69     # `tf.debugging.disable_traceback_filtering()`
---> 70     raise e.with_traceback(filtered_tb) from None
     71 finally:
     72     del filtered_tb

File /tmp/__autograph_generated_fileau_h0p6f.py:15, in outer_factory.<locals>.inner_factory.<locals>.tf__predict_function(iterator)
     13 try:
     14     do_return = True
---> 15     retval_ = ag__.converted_call(ag__.ld(step_function), (ag__.ld(self), ag__.ld(iterator)), None, fscope)
     16 except:
     17     do_return = False

NotImplementedError: in user code:

    File "/notebooks/users/1004831/objupyterlabgpu-1004831/kernels/mytensor2.0.0b/lib/python3.9/site-packages/keras/engine/training.py", line 2041, in predict_function  *
        return step_function(self, iterator)
    File "/notebooks/users/1004831/objupyterlabgpu-1004831/kernels/mytensor2.0.0b/lib/python3.9/site-packages/keras/engine/training.py", line 2027, in step_function  **
        outputs = model.distribute_strategy.run(run_step, args=(data,))
    File "/notebooks/users/1004831/objupyterlabgpu-1004831/kernels/mytensor2.0.0b/lib/python3.9/site-packages/keras/engine/training.py", line 2015, in run_step  **
        outputs = model.predict_step(data)
    File "/notebooks/users/1004831/objupyterlabgpu-1004831/kernels/mytensor2.0.0b/lib/python3.9/site-packages/keras/engine/training.py", line 1983, in predict_step
        return self(x, training=False)
    File "/notebooks/users/1004831/objupyterlabgpu-1004831/kernels/mytensor2.0.0b/lib/python3.9/site-packages/keras/utils/traceback_utils.py", line 70, in error_handler
        raise e.with_traceback(filtered_tb) from None
    File "/notebooks/users/1004831/objupyterlabgpu-1004831/kernels/mytensor2.0.0b/lib/python3.9/site-packages/keras/engine/training.py", line 584, in call
        raise NotImplementedError(

    NotImplementedError: Exception encountered when calling layer "vae_6" "                 f"(type VAE).
    
    Unimplemented `tf.keras.Model.call()`: if you intend to create a `Model` with the Functional API, please provide `inputs` and `outputs` arguments. Otherwise, subclass `Model` with an overridden `call()` method.
    
    Call arguments received by layer "vae_6" "                 f"(type VAE):
      • inputs=tf.Tensor(shape=(None, 20, 1), dtype=float32)
      • training=False
      • mask=None

我的初始代码在这里
第一次
这意味着子类，API的问题，但我不能理解的问题。我怎么做，以修复我的代码计算列车损失？