%pip stopped working in Pythonista Lab version 1.0 (8)

[RichardPotthoff]

When I enter %pip in the Pythonista Lab console, I get the following error message:

!/private/var/containers/Bundle/Application/E8FAD0F9-1BCC-44DB-A84E-6ECE2285DE30/PythonistaLab.app/PythonistaLab -m pip 
PythonistaLab: command not found

Note: you may need to restart the kernel to use updated packages.

The command worked initially in the current Pythonista Lab version 1.0 (8), and I was able to install additional site-packages. Apparently one of the packages I installed interferes with the Pythonista Lab installation.
Pythonista Lab 1.0 (7) had the same problem.
Restarting the kernel (by closing and re-opening the app) did not help.

[RichardPotthoff]

For now I have a work around:

def sh_cmd(cmdln):
  import sys
  import shlex
  saved_argv=sys.argv
  sys.argv=shlex.split(cmdln)
  try:
    if sys.argv[0]=='pip':
      from pip._internal.cli.main import main as _main
      return(_main())
  finally:
    sys.argv=saved_argv

This works, but there seem to be built-in site packages that are only partially installed, e.g.:

• fontTools (No module named 'fontTools')
• jsonschema (No module named 'rpds')
• setuptools (No module named '_distutils_hack')

When I try to install the missing fonttools package:

sh_cmd("pip install fonttools")
import fontTools

I get the following error:

Defaulting to user installation because normal site-packages is not writeable
Requirement already satisfied: fonttools in /var/containers/Bundle/Application/E8FAD0F9-1BCC-44DB-A84E-6ECE2285DE30/PythonistaLab.app/Frameworks/Py3Kit.framework/pylib/site-packages (4.55.6)
Exception in execute request:
---------------------------------------------------------------------------
ModuleNotFoundError                       Traceback (most recent call last)
Cell In[47], line 2
      1 sh_cmd("pip install fonttools")
----> 2 import fontTools

ModuleNotFoundError: No module named 'fontTools'
---------------------------------------------------------------------------
ModuleNotFoundError                       Traceback (most recent call last)
Cell In[47], line 2
      1 sh_cmd("pip install fonttools")
----> 2 import fontTools

ModuleNotFoundError: No module named 'fontTools'

I got rid of the "no module named rpds" error by installing an older version of jsonschema:

sh_cmd("pip install jsonschema==3.2.0");

The installation succeeds, but I get a few warnings:

Defaulting to user installation because normal site-packages is not writeable
Collecting jsonschema==3.2.0
  Using cached jsonschema-3.2.0-py2.py3-none-any.whl.metadata (7.8 kB)
Requirement already satisfied: attrs>=17.4.0 in /var/containers/Bundle/Application/E8FAD0F9-1BCC-44DB-A84E-6ECE2285DE30/PythonistaLab.app/Frameworks/Py3Kit.framework/pylib/site-packages (from jsonschema==3.2.0) (24.2.0)
Requirement already satisfied: pyrsistent>=0.14.0 in /var/containers/Bundle/Application/E8FAD0F9-1BCC-44DB-A84E-6ECE2285DE30/PythonistaLab.app/Frameworks/Py3Kit.framework/pylib/site-packages (from jsonschema==3.2.0) (0.20.0)
Requirement already satisfied: setuptools in /var/containers/Bundle/Application/E8FAD0F9-1BCC-44DB-A84E-6ECE2285DE30/PythonistaLab.app/Frameworks/Py3Kit.framework/pylib/site-packages (from jsonschema==3.2.0) (75.8.2)
Requirement already satisfied: six>=1.11.0 in /var/containers/Bundle/Application/E8FAD0F9-1BCC-44DB-A84E-6ECE2285DE30/PythonistaLab.app/Frameworks/Py3Kit.framework/pylib/site-packages (from jsonschema==3.2.0) (1.17.0)
Using cached jsonschema-3.2.0-py2.py3-none-any.whl (56 kB)
Installing collected packages: jsonschema
Successfully installed jsonschema-3.2.0
  WARNING: The script jsonschema is installed in '/var/mobile/Containers/Data/Application/89CCB253-4128-4E6A-80AE-6C96FB83A729/Documents/bin' which is not on PATH.
  Consider adding this directory to PATH or, if you prefer to suppress this warning, use --no-warn-script-location.
ERROR: pip's dependency resolver does not currently take into account all the packages that are installed. This behaviour is the source of the following dependency conflicts.
jupyter-events 0.12.0 requires jsonschema[format-nongpl]>=4.18.0, but you have jsonschema 3.2.0 which is incompatible.
jupyterlab-server 2.27.3 requires jsonschema>=4.18.0, but you have jsonschema 3.2.0 which is incompatible.

Despite the warning, some of the modules that could not be imported because of the "No module named 'rpds'"-error are now working: e.g. nbformat.