How to train with multi GPUs?

[HoJ-Onle]

Hello! I tried to train the model with multi GPUs. And I found that you have released train_distributed.py
So I tried to use tf.distribute.MirroredStrategy() as strategy to achieve distributed training. But I got an error as follows:

 RuntimeError: `merge_call` called while defining a new graph or a tf.function. This can often happen if the function `fn` passed to `strategy.experimental_run()` is decorated with `@tf.function` (or contains a nested `@tf.function`), and `fn` contains a synchronization point, such as aggregating gradients. This behavior is not yet supported. Instead, please wrap the entire call `strategy.experimental_run(fn)` in a `@tf.function`, and avoid nested `tf.function`s that may potentially cross a synchronization boundary.

Looking forward to your help!!