Unfortunately, I’m not quite sure what might be going on.
Regarding installing the IPython interpreter itself (prior to installing PyRosetta), this forum is probably not the best place to troubleshoot it. I’d recommend looking at the help forums dedicated to your distribution. (e.g. for Ubuntu you can try https://askubuntu.com/)
If you don’t have a good installation of Python, then trying to install PyRosetta isn’t going to work well, so I’d recommend making sure your Python installation is up and running first before troubleshooting the PyRosetta install.
Regarding the test failures, debugging that would require more information (such as what the error message is), but the issue discussed in the linked post (that the version of PyRosetta you download has to match the version of Python you’re using), is a reasonable guess, particularly given you were having issues installing Python itself.
In short, make sure your Python install is working first, then make sure you’re installing the correct version of PyRosetta for that version of Python.
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