Resolving Errors When Loading the lldb Debugger

From time to time, I work with C code, and I use the lldb debugger to step through the code. Recently, after a Mac OS update, I started seeing this error when attempting to start the lldb debugger in terminal:

$ lldb
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/local/Cellar/llvm/15.0.7_1/libexec/python3.11/site-packages/lldb/__init__.py", line 96, in <module>
    import six
ModuleNotFoundError: No module named 'six'

The error message says that a module (six) is missing. The other issue, is that this module is missing on a version of python that is not the global version set by pyenv. I check the versions of pyenv on my system:

$ pyenv versions
  system
* 3.8.16 (set by /Users/<username>/.pyenv/version)
  3.9.1
  3.11.2

I’m guessing lldb uses the system version of Python. A simple pip3 install six will not fix the issue, since this will install this package for Python 3.8.16, instead of the system version. I now use pyenv to set the local version of python to system:

$ pyenv local system
$ pyenv versions
* system (set by /Users/<username>/.python-version)
  3.8.16
  3.9.1
  3.11.2

I now install six:

$ pip3 install six
Collecting six
  Using cached six-1.16.0-py2.py3-none-any.whl (11 kB)
Installing collected packages: six
Successfully installed six-1.16.0

And I try launching lldb on terminal again:

% lldb
(lldb)

.. which takes me to the (lldb) prompt without any issues.

Make sure you “reset” the default python version to be used to the version you had before (in my case this would be version 3.8.16)