Pytorch frontend: no module named packaging

Troubleshooting
#1

I found pytorch frontend failed because of packaging module not found. is there anyone know the reason?

the commit ID is 7ccb4363eefa76ae355ee263aa5527d43fb699fb

 Executing task: python3 tutorials/frontend/from_pytorch.py <

Traceback (most recent call last):

  File "/workspace/tutorials/frontend/from_pytorch.py", line 45, in <module>
    from tvm import relay

  File "/workspace/python/tvm/relay/__init__.py", line 51, in <module>
    from . import frontend

  File "/workspace/python/tvm/relay/frontend/__init__.py", line 39, in <module>
    from .pytorch import from_pytorch

  File "/workspace/python/tvm/relay/frontend/pytorch.py", line 22, in <module>
    from packaging import version

ModuleNotFoundError: No module named 'packaging'

The terminal process terminated with exit code: 1

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#2

Sorry I thought packaging was one of the standard python libs. If we agree that we don’t support Torch 1.2 or older, we can remove this dependency. For now, pip install packaging should solve it.

cc @alexwong

#3

I could see supporting only one version being less confusing for users (always up to date or one release behind) so I would be for it.