Hello, I am picking up an old code that used chimera and updating it to use ChimeraX. Our code writes a python script file that looks like : import chimera from chimera import runCommand runCommand("open ../4ZKC_H_reduce.pdb") runCommand("swapaa LYS #0:11.B&:LYS lib dynameomics") runCommand("swapaa TRP #0:51.B&:TRP lib dynameomics") runCommand("write #0 ../4ZKC_H_reduce.pdb") and executes chimera --nogui --nostatus --script python_script.py I installed ChimeraX on Ubuntu 22.01 with the .deb from your website and "sudo apt install chimerax.deb" When i execute ChimeraX with my script, i get : available bundle cache has not been initialized yet Executing: runscript chim_4ZKC_H_reduce.py Traceback (most recent call last): File "chim_4ZKC_H_reduce.py", line 2, in <module> from chimera import runCommand ModuleNotFoundError: No module named 'chimera' Traceback (most recent call last): File "/usr/lib/ucsf-chimerax/lib/python3.9/site-packages/chimerax/core/scripting.py", line 84, in open_python_script _exec_python(session, code, argv) File "/usr/lib/ucsf-chimerax/lib/python3.9/site-packages/chimerax/core/scripting.py", line 61, in _exec_python exec(code, sandbox.__dict__) File "chim_4ZKC_H_reduce.py", line 2, in <module> from chimera import runCommand ModuleNotFoundError: No module named 'chimera' During handling of the above exception, another exception occurred: Traceback (most recent call last): File "/usr/lib/ucsf-chimerax/lib/python3.9/site-packages/chimerax/core/__main__.py", line 747, in init run(sess, 'runscript %s' % script) File "/usr/lib/ucsf-chimerax/lib/python3.9/site-packages/chimerax/core/commands/run.py", line 38, in run results = command.run(text, log=log, return_json=return_json) File "/usr/lib/ucsf-chimerax/lib/python3.9/site-packages/chimerax/core/commands/cli.py", line 2897, in run result = ci.function(session, **kw_args) File "/usr/lib/ucsf-chimerax/lib/python3.9/site-packages/chimerax/core/commands/runscript.py", line 38, in runscript open_python_script(session, open(script_file, 'rb'), script_file, argv=argv) File "/usr/lib/ucsf-chimerax/lib/python3.9/site-packages/chimerax/core/scripting.py", line 90, in open_python_script raise UserError('Error opening python file %s' % stream.name) chimerax.core.errors.UserError: Error opening python file chim_4ZKC_H_reduce.py I tried installing chimera using pip but it installs Chimera (the one in python 2.7) and crashes during the installation. Any ideas on how to fix this? Did i do something wrong somewhere? Thanks you very much for your help, Bar Collignon