Seems like an environment issue, but when i run the same command from terminal it is working fine, so it is hard to debug.
Any input would be appreciated.
See image below

@vladamx is there by any chance non ascii tokens inside your device name?
@jknoxville looks like a charset issue. Is this a known limitation from idb?
Yes, this was the problem.
brew reinstall grpc worked for me
I'm having the same error, I do not have ascii tokens in my device name. Running the above suggested brew command did not fix my problem either.
> python -V
Python 2.7.16
brew reinstall grpcworked for me
This solved it for me.