slpkg issues

i simply want to update an old version of slpkg on my slack150 box(es) and that's when the update/upgrade nirwana begins. ultimately i just need a new version of signal_desktop i wanted to use slpkg for, but that's just on the side for now...

on a first slack150 machine with slpkg 4.2 i was able to upgrade to 4.9.7 (as required for the signal_desktop upgrade) - but then on my 2nd slack150 box with an even older slpkg version 3.9.1 that ipsigenic upgrade of slpkg itself does not work anymore. after updating or freshly installing half a dozen or so SBo packages i seem to be stuck with the following issues - mainly 'tomli' :

Code:./python3-tomli_w.SlackBuild
tomli_w-1.0.0/LICENSE
tomli_w-1.0.0/README.md
tomli_w-1.0.0/pyproject.toml
tomli_w-1.0.0/tomli_w/__init__.py
tomli_w-1.0.0/tomli_w/_writer.py
tomli_w-1.0.0/tomli_w/py.typed
tomli_w-1.0.0/PKG-INFO
Traceback (most recent call last):
File "/usr/lib64/python3.7/runpy.py", line 183, in _run_module_as_main
mod_name, mod_spec, code = _get_module_details(mod_name, _Error)
File "/usr/lib64/python3.7/runpy.py", line 142, in _get_module_details
return _get_module_details(pkg_main_name, error)
File "/usr/lib64/python3.7/runpy.py", line 109, in _get_module_details
__import__(pkg_name)
File "/usr/lib64/python3.7/site-packages/build/__init__.py", line 40, in <module>
import tomli as tomllib
ModuleNotFoundError: No module named 'tomli'Code:pip3 install --upgrade tomli
Segmentation faultCode:./slpkg.SlackBuild
slpkg-4.9.7/
slpkg-4.9.7/.gitignore
...
slpkg-4.9.7/tools/
slpkg-4.9.7/tools/gen_sbo_txt.sh
Traceback (most recent call last):
File "/usr/lib64/python3.7/runpy.py", line 183, in _run_module_as_main
mod_name, mod_spec, code = _get_module_details(mod_name, _Error)
File "/usr/lib64/python3.7/runpy.py", line 142, in _get_module_details
return _get_module_details(pkg_main_name, error)
File "/usr/lib64/python3.7/runpy.py", line 109, in _get_module_details
__import__(pkg_name)
File "/usr/lib64/python3.7/site-packages/build/__init__.py", line 40, in <module>
import tomli as tomllib
ModuleNotFoundError: No module named 'tomli'Code:slpkg -h
Traceback (most recent call last):
File "/usr/bin/slpkg", line 35, in <module>
from slpkg.main import main
ModuleNotFoundError: No module named 'slpkg'why does such a slpkg upgrade have to be so painfully complicated ??? i usually keep it simple and just use plain SBo scripts with install/removepkg - but occasionally i would want to enjoy the comfort of an automated slackware package manager, for example in the case of upgrading this signal_desktop package...