Error: The network has multiple inputs, and saving such result han't been implemented.

[MustafaHull]

I am testing the simple example of antiderivative DeepONet, the run was successful up to the training stage, but after that, two-error come out:

Parameters: 7401

Saving loss history to C:\Users\Dell\OneDrive - hull.ac.uk\Wave Eneergy Work\deeponet-master\src\loss.dat ...
Error: The network has multiple inputs, and saving such result han't been implemented.
Error: The network has multiple inputs, and plotting such result han't been implemented.

the full output is as below:
================================== RESTART: C:\Users\Dell\OneDrive - hull.ac.uk\Wave Eneergy Work\deeponet-master\src\deeponet_pde.py =================================
WARNING:tensorflow:From C:\Users\Dell\AppData\Local\Programs\Python\Python39\lib\site-packages\keras\src\losses.py:2976: The name tf.losses.sparse_softmax_cross_entropy is deprecated. Please use tf.compat.v1.losses.sparse_softmax_cross_entropy instead.

Using backend: tensorflow.compat.v1
Other supported backends: tensorflow, pytorch, jax, paddle.
paddle supports more examples now and is recommended.
WARNING:tensorflow:From C:\Users\Dell\AppData\Local\Programs\Python\Python39\lib\site-packages\deepxde\backend\tensorflow_compat_v1\tensor.py:25: The name tf.disable_v2_behavior is deprecated. Please use tf.compat.v1.disable_v2_behavior instead.

WARNING:tensorflow:From C:\Users\Dell\AppData\Local\Programs\Python\Python39\lib\site-packages\tensorflow\python\compat\v2_compat.py:108: disable_resource_variables (from tensorflow.python.ops.variable_scope) is deprecated and will be removed in a future version.
Instructions for updating:
non-resource variables are not supported in the long term
Generating operator data...
'gen_operator_data' took 175.005780 s

Generating operator data...
'gen_operator_data' took 1317.193413 s

Compiling model...
Building DeepONet...

Warning (from warnings module):
File "C:\Users\Dell\AppData\Local\Programs\Python\Python39\lib\site-packages\deepxde\nn\tensorflow_compat_v1\deeponet.py", line 367
return tf.layers.dense(
UserWarning: tf.layers.dense is deprecated and will be removed in a future version. Please use tf.keras.layers.Dense instead.
WARNING:tensorflow:From C:\Users\Dell\AppData\Local\Programs\Python\Python39\lib\site-packages\keras\src\utils\version_utils.py:76: The name tf.executing_eagerly_outside_functions is deprecated. Please use tf.compat.v1.executing_eagerly_outside_functions instead.

'build' took 5.074972 s

WARNING:tensorflow:From C:\Users\Dell\AppData\Local\Programs\Python\Python39\lib\site-packages\deepxde\model.py:168: The name tf.train.Saver is deprecated. Please use tf.compat.v1.train.Saver instead.

'compile' took 6.762535 s

Warning: epochs is deprecated and will be removed in a future version. Use iterations instead.
Training model...

Step Train loss Test loss Test metric
0 [3.76e-01] [3.60e-01] [3.52e-01]
1000 [4.29e-04] [4.69e-04] [4.56e-04]
2000 [1.25e-04] [1.39e-04] [1.34e-04]
3000 [1.00e-04] [1.13e-04] [1.09e-04]
4000 [8.92e-05] [1.01e-04] [9.80e-05]
5000 [5.04e-05] [5.87e-05] [5.63e-05]
6000 [3.15e-05] [3.60e-05] [3.46e-05]
7000 [4.05e-05] [4.37e-05] [4.25e-05]
8000 [1.95e-05] [2.28e-05] [2.20e-05]
9000 [1.47e-05] [1.74e-05] [1.66e-05]
10000 [1.75e-05] [1.92e-05] [1.86e-05]
11000 [9.42e-06] [1.08e-05] [1.03e-05]
12000 [1.26e-05] [1.42e-05] [1.37e-05]
13000 [9.21e-06] [1.03e-05] [9.92e-06]
14000 [7.55e-06] [8.85e-06] [8.50e-06]
15000 [6.43e-06] [7.31e-06] [6.99e-06]
16000 [5.47e-06] [6.34e-06] [6.03e-06]
17000 [1.16e-05] [1.23e-05] [1.19e-05]
18000 [5.36e-06] [5.94e-06] [5.66e-06]
19000 [1.50e-05] [1.59e-05] [1.54e-05]
20000 [1.31e-05] [1.37e-05] [1.33e-05]
21000 [6.99e-06] [7.27e-06] [6.98e-06]
22000 [4.51e-06] [5.00e-06] [4.75e-06]
23000 [5.36e-06] [5.76e-06] [5.50e-06]
24000 [3.44e-06] [3.88e-06] [3.65e-06]
25000 [3.16e-06] [3.58e-06] [3.36e-06]
26000 [2.91e-06] [3.32e-06] [3.10e-06]
27000 [5.88e-06] [6.15e-06] [5.90e-06]
28000 [2.64e-06] [3.01e-06] [2.80e-06]
29000 [3.09e-06] [3.39e-06] [3.17e-06]
30000 [4.71e-06] [5.00e-06] [4.75e-06]
31000 [4.15e-06] [4.48e-06] [4.24e-06]
32000 [4.32e-06] [4.51e-06] [4.29e-06]
33000 [8.34e-06] [8.66e-06] [8.32e-06]
34000 [6.72e-06] [6.95e-06] [6.67e-06]
35000 [2.59e-06] [2.92e-06] [2.70e-06]
36000 [3.08e-06] [3.39e-06] [3.18e-06]
37000 [6.25e-06] [6.55e-06] [6.27e-06]
38000 [3.51e-06] [3.87e-06] [3.64e-06]
39000 [9.01e-06] [8.83e-06] [8.56e-06]
40000 [5.93e-06] [6.09e-06] [5.84e-06]
41000 [2.43e-06] [2.73e-06] [2.53e-06]
42000 [2.13e-06] [2.38e-06] [2.17e-06]
43000 [2.82e-06] [3.08e-06] [2.87e-06]
44000 [2.48e-06] [2.82e-06] [2.60e-06]
45000 [1.81e-06] [2.11e-06] [1.90e-06]
46000 [1.91e-06] [2.19e-06] [1.99e-06]
47000 [1.75e-06] [2.05e-06] [1.84e-06]
48000 [5.09e-06] [5.44e-06] [5.17e-06]
49000 [8.45e-06] [8.69e-06] [8.39e-06]
50000 [2.91e-06] [3.27e-06] [3.04e-06]

Best model at step 47000:
train loss: 1.75e-06
test loss: 2.05e-06
test metric: [1.84e-06]

'train' took 1599.060037 s

Parameters: 7401

Saving loss history to C:\Users\Dell\OneDrive - hull.ac.uk\Wave Eneergy Work\deeponet-master\src\loss.dat ...
Error: The network has multiple inputs, and saving such result han't been implemented.
Error: The network has multiple inputs, and plotting such result han't been implemented.