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Hi,
I have been trying to figure out which Python versions are compatible with LEAN CLI and there seems to be missing/contradicting information in the docs/github/pypi.
The docs doesn't seem to refer to any kind of python version requirement:
the docs related to installing LEAN Engine is empty:
However in LEAN github repo under Algorithm.Python this is stated:
“Setup Lean Locally with Python … Installing Python 3.6: … Use the Windows x86-64 MSI Python 3.6.8 installer from python.org or Anaconda for Windows installer. … Install pandas=0.25.3 and its dependencies…”
But then again in the Lean CLI github repo, there is no mention of any Python version requirement:
However on Pypi it is stated as Requires: Python >= 3.6
Am I mixing up LEAN CLI vs Engine requirements? If the CLI requirement is just Python ≥3.6, can I backtest a machine learning model trained with a package that requires Python 3.8 work? Any clarification and info is greatly appreciated!
Note: I am thinking of using LEAN only locally. I think there are other package and Python version limitations when using LEAN on QuantConnect Cloud.
Fred Painchaud
Hi Notta,
I had and seen people have problems while installing LEAN CLI with Python 3.10. I don't recommend.
I used Python 3.6, 3.7, 3.8 and 3.9 without any issues.
Fred
Nottakumasato
Fred Painchaud was just able to run a backtest in a virtual environment with Python 3.9.12 without any problem. And the logs show that the docker image has Python 3.6.8 so I guess Python version requirement is only for the docker image not for LEAN CLI. Thanks!
Nottakumasato
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