Can't install via pip

[gerritzen]

The install fails with the message

$ pip install mobi
Defaulting to user installation because normal site-packages is not writeable
Collecting mobi
  Using cached mobi-0.3.3.tar.gz (90 kB)
  Preparing metadata (pyproject.toml) ... err
or
  error: subprocess-exited-with-error
  
  × Preparing metadata (pyproject.toml) did n
ot run successfully.
  │ exit code: 1
  ╰─> [57 lines of output]
      Traceback (most recent call last):
        File "/var/mobile/Containers/Data/App
lication/1D580812-9B84-4283-9271-4A44EFA09D9B
/Library/lib/python3.11/site-packages/pip/_ve
ndor/pyproject_hooks/_in_process/_in_process.
py", line 353, in <module>
          main()
        File "/var/mobile/Containers/Data/App
lication/[...]
/Library/lib/python3.11/site-packages/pip/_ve
ndor/pyproject_hooks/_in_process/_in_process.
py", line 335, in main
          json_out['return_val'] = hook(**hoo
k_input['kwargs'])
[...]
        File "/var/mobile/Containers/Data/App
lication/[...]
/Library/lib/python3.11/site-packages/poetry/
core/_vendor/tomlkit/items.py", line 1771, in
 __init__
          super().__init__(trivia)
      TypeError: object.__init__() takes exac
tly one argument (the instance to initialize)
      [end of output]
  
  note: This error originates from a subproce
ss, and is likely not a problem with pip.
error: metadata-generation-failed

I'm using a-Shell and

$ pip --version
pip 23.0.1 from /var/mobile/Containers/Data/A
pplication/[...]/Library/lib/python3.11/site-packages/pip (
python 3.11)