Add `enum34` in `setup.py`

[Hector]

Describe the bug
In one of the prior PR we introduces enum package and didn't add the installation entry to the setup.py.

Expected behavior
enum34 should be installed with setup.py.

Screenshots
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Environment (please complete the following information):

• OS: [e.g. iOS]
• Version [e.g. 22]
• Python and Package verions: [e.g. Python version, Pytorch version]

Additional context
Add any other context about the problem here.