Fix for "module 'torch' has no attribute 'io'" when encoding audio/video. Use when:
(1) Using torchaudio.save() or torchvision.save(), (2) Need to encode tensors to
in-memory bytes, (3) Getting AttributeError: module 'torch' has no attribute 'io'.
Solution: Use Python's built-in io.BytesIO, not torch.io.BytesIO.