Installation requires wrong (?) version of cattrs (MacOS)

Unity Engine
,
1

Hey there,

Just a quick note on the installation experience - I installed mlagents via pip as instructed, but it wouldn’t run. After some digging I discovered this was because I had the wrong version of cattrs. However when I tried to install 1.1.1 pip warned me that mlagents actually requires 1.1.0 or less.

I’m not sure if this is because 1.1.1 is new and thus mlagents’ package list hasn’t been updated, or if 1.1.1 specifically breaks something in mlagents I’m not aware of yet. But the 1.0.0 version, which mlagents accepts, did not allow mlagents --help to run because of an error in the typing library.

Hope this helps? Sorry if it’s a bit vague. This is a little out of my area.

2

Hi,
What version of python are you using? cattrs 1.0.x doesn’t seem to support python 3.9 (which is my guess for your version).
We currently have mlagents requiring “<1.1.0” because 1.1.0 dropped support for python 3.6.

If you’re able to get things running with cattrs 1.1.1 despite pip warnings, I think you’ll be fine. You might want to consider downgrading to python 3.8 if possible, though, since not all of our other dependencies might support it right now.

3

I’m trying to get a suitable combination of cattrs versions (and python3.9 in general) running here: Update cattrs dependencies to support python3.9 by chriselion · Pull Request #4821 · Unity-Technologies/ml-agents · GitHub