[BUG]: Failed to customize and let PySR use the modified backend.

[jun199704]

What happened?

I'm trying to customize and let PySR use the modified backend according to instructions in https://astroautomata.com/PySR/backend/.
But getting errors as shown follows:
ERROR: Ignored the following yanked versions: 0.4.1, 0.5.0
ERROR: Ignored the following versions that require a different python version: 0.9.20 Requires-Python ~=3.8
ERROR: Could not find a version that satisfies the requirement juliacall==0.9.20 (from pysr) (from versions: 0.4.2, 0.4.3, 0.5.1, 0.6.0, 0.6.1, 0.8.0, 0.9.0, 0.9.1, 0.9.2, 0.9.3, 0.9.4, 0.9.5, 0.9.6, 0.9.7, 0.9.8, 0.9.9, 0.9.10, 0.9.11, 0.9.12, 0.9.13, 0.9.14, 0.9.15, 0.9.16, 0.9.17, 0.9.18, 0.9.19)
ERROR: No matching distribution found for juliacall==0.9.20

Version

pysr version: 0.18.3

Operating System

Linux

Package Manager

pip

Interface

Script (i.e., python my_script.py)

Relevant log output

Processing /home/perception/Jun/PySR
  Installing build dependencies ... done
  Getting requirements to build wheel ... done
  Installing backend dependencies ... done
  Preparing metadata (pyproject.toml) ... done
Requirement already satisfied: sympy<2.0.0,>=1.0.0 in /home/perception/anaconda3/envs/CAVperception/lib/python3.7/site-packages (from pysr==0.18.5) (1.10.1)
Requirement already satisfied: pandas<3.0.0,>=0.21.0 in /home/perception/anaconda3/envs/CAVperception/lib/python3.7/site-packages (from pysr==0.18.5) (1.3.5)
Requirement already satisfied: numpy<2.0.0,>=1.13.0 in /home/perception/anaconda3/envs/CAVperception/lib/python3.7/site-packages (from pysr==0.18.5) (1.21.5)
Requirement already satisfied: scikit-learn<2.0.0,>=1.0.0 in /home/perception/anaconda3/envs/CAVperception/lib/python3.7/site-packages (from pysr==0.18.5) (1.0.2)
INFO: pip is looking at multiple versions of pysr to determine which version is compatible with other requirements. This could take a while.
ERROR: Ignored the following yanked versions: 0.4.1, 0.5.0
ERROR: Ignored the following versions that require a different python version: 0.9.20 Requires-Python ~=3.8
ERROR: Could not find a version that satisfies the requirement juliacall==0.9.20 (from pysr) (from versions: 0.4.2, 0.4.3, 0.5.1, 0.6.0, 0.6.1, 0.8.0, 0.9.0, 0.9.1, 0.9.2, 0.9.3, 0.9.4, 0.9.5, 0.9.6, 0.9.7, 0.9.8, 0.9.9, 0.9.10, 0.9.11, 0.9.12, 0.9.13, 0.9.14, 0.9.15, 0.9.16, 0.9.17, 0.9.18, 0.9.19)
ERROR: No matching distribution found for juliacall==0.9.20

Extra Info

No response

[MilesCranmer]

Perhaps you can try uninstalling everything and then reinstalling?