AttributeError: Can't pickle local object 'AudioToBPEDataset.__init__.<locals>.TokenizerWrapper'
Hi, I can not run transcribe audio method using STT En Conformer-CTC Small model on windows 10.
I am using the following code: 
```
import nemo.collections.asr as nemo_asr

asr_model = nemo_asr.models.EncDecCTCModelBPE.restore_from("models/stt_en_conformer_ctc_small.nemo")

files = ['1.wav']

print(asr_model.transcribe(files, batch_size=1))
```
I'm using branch r1.5.0
As a result, I get the following error: 
**AttributeError: Can't pickle local object 'AudioToBPEDataset\.\_\_init\_\_.\<locals\>\.TokenizerWrapper'**

On the colab everything worked without problems. What could be the problem and how to solve it? Thank you. 