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Specify a path for ctypes.util.find_library() under macOS

I'd like to specify a path for ctypes.util.find_library() to search. How can I do this?
I'd like to do it from within Python.
I'm using macOS.
If I wanted to do it from outside Python, I can specify the location using LD_LIBRARY_PATH. However I have read that I cannot modify this environment variable from within Python as it is cached on Python's startup. Modifying the value and then restarting Python seems like a very unusable idea; for example, what would happen if the library was imported part way through execution?
Why would I like to do this? Because I would like to add a MacOS wheel to a Python library that works under Windows. Currently they're packaging the DLLs into the same directory as the Python source files and adding that path to Windows' PATH environment, which ctypes.util.find_library() searches--a technique that I can't seem to replicate under Mac.
I have tried to understand delocate. It seems to state that the Python library doesn't depend on any shared objects. I suspect this is because the dylibs are loaded dynamically using ctypes.util.find_library() rather than being compiled code within Python.
Any suggestions would be gratefully received!

Although there are environment variables (LD_LIBRARY_PATH and DYLD_LIBRARY_PATH) that impact the search path for shared libraries, they are read and fixed by Python when Python starts up. Thus that option was eliminated.
Instead, we took the approach hinted at in the Python documentation:
If wrapping a shared library with ctypes, it may be better to determine the shared library name at development time, and hardcode that into the wrapper module instead of using find_library() to locate the library at runtime.
We hard-coded the names of the libraries that were included for each operating system, plus we included a generic name for operating systems where the libraries were not included:
names = {
"Windows": "libogg.dll",
"Darwin": "libogg.0.dylib",
"external": "ogg"
}
The library loading code checks if it can find the specified library for the current operating system. If it isn't successful, a search is made for the 'external' library.
The library loading code can be found inside the PyOgg project; see Library.load().
Further to this, inspired by the delocate project, we were required to edit the paths found inside certain dylibs. For example, we edited the opusfile binary to point to the ogg binary found in our package:
install_name_tool -change /usr/local/opt/libogg/lib/libogg.0.dylib #loader_path/libogg.0.dylib libopusfile.0.dylib
For the details on this process please see the README file associated with the macOS binaries inside the PyOgg project.
Further discussion of the approach can be found in the issue raised on PyOgg's GitHub page (#32).

Missing classes from qgis.core module only in PyCharm's editor

I would like to use PyCharm Community Edition 2020.1.2 x64 on Windows 10 as IDE for writing QGIS plugins. I need to base on old version - QGIS 2.18, so I need python 2.7, qt4, and also core modules from QGIS 2.18. I downloaded QGIS 2.18 from official site. It provides a ready to use python environment as .bat script, that sets all needed python paths. So I used path D:\Program Files\QGIS 2.18\bin\python-qgis-ltr.bat to set main python interpreter for my project.
After that I was able to run python console in PyCharm, import all QGIS modules, and any classes from QGIS standard collection like QgsFeature, QgsVectorLayer etc. Everything was fine untill I tried to import this classes from PyCharm editor in .py file as from qgis.core import QgsFeature. In editor PyCharm sees the package qgis.core and I'm able to import it, but PyCharm's code completion inside the module sees only classes that are saved in D:\Program Files\QGIS 2.18\apps\qgis-ltr\python\qgis\core\__init__.py e.g. QgsEditError class, but all standard QGIS class underlines on red.
Python console ran on exactly the same interpreter see the same sources as are visible in "External Libraries" tab in PyCharm, so command:
qgis.core.__path__ returns ['D:\\Program Files\\QGIS 2.18\\apps\\qgis-ltr\\python\\qgis\\core'],
qgis.core.__file__ returns 'D:\\Program Files\\QGIS 2.18\\apps\\qgis-ltr\\python\\qgis\\core\\__init__.pyc,
dir(qgis.core) returns full list of QGIS standard core classes.
If I run the .py script, in which PyCharm's code validator is showing incorrect import object by red underline, the script is executed without any error and I can easly print the imported QgsFeature object. Why my PyCharm's editor see different content of qgis.core module then console ran also from IDE on exactly the same interpreter?

Allow me to qualify myself. I lost interest for adventures and trail blazing in computing some time ago. I won some big battles and lost some too. And I unnecessary wasted a lot of time that could have been better spent. Nowadays, I just wait a reasonable period of time before upgrading anything, and wait a spell before downloading the newest anything, and pretty much avoid trying to do things outside a conventional path.
So your post got me curious and I looked around some. I found very little information about PyCharm being used building QGIS plugins. That pretty much tells me all I want to know: that it's not real common for PyCharm to be used in building QGIS plugins.
But there was quite abit of information about building QGIS plugins with python. There's even a QGIS Tutorial & Tips on the subject. QGIS suggests using the Qt Creator and further goes on to say that QGIS itself is written using the QT framework. "For plugin development, we use an application called Qt Creator."
If you overcome your current predicament I'd like to hear how you accomplished it.
For what it's worth, here's the link to the QGIS Tutorials & Tips.
https://www.qgistutorials.com/en/docs/building_a_python_plugin.html

Finally, the problem solved itself. It was something wrong with building a binary skeletons of C++ libraries, what PyCharm does every time the application is launched. My PyCharm didn't want to do it and I found many similar problems with other libraries (e.g. Qt) that people were struggling with. After two days my PyCharm just fixed itself and created all needed binary skeletons for my QGIS libraries.

libselinux-python bindings and ansible

Sorry for answering my own question, but I've seen this crop up in multiple forums, so I wanted to post this in hope it helps someone else.
The basic problem occurs when trying to run Ansible against older Python interpreters -- particularly Python 2.6 on RedHat 5 -- and getting error messages about 'libselinux bindings not available' or similar errors.
While this could happen for any Python-based application, I see it most commonly on Ansible. Ansible presumes the selinux module is available and will always attempt to import it at runtime.

The libselinux-python bindings are not a simple python module. The module must be cross-compiled against both the target version of Python and the target version of libselinux. The nice folks maintaining the RedHat 5 EPEL repositories did not generate a Python 2.6/libselinux 1.33 module.
The 'existing' libselinux-python module from the standard repos will not work, because it is specific to the supplied Python 2.4 interpreter. If you copied the module from a different Python 2.6 install -- say, a RedHat 6 system -- that won't work either, because it's built against the wrong version of libselinux. While you can amuse yourself with the various errors created by different combinations, Ansible won't bother to distinguish between them; it will just state that the bindings are unavailable.
The solution is to create a 'stub' selinux python module to pacify Ansible. Create a file
/usr/lib64/python2.6/site-packages/selinux/__init__.py
with the following contents:
def is_selinux_enabled():
return False
def is_selinux_mls_enabled():
return False
(This is Python code, so mind the indents.) This effectively disables Ansible from working with selinux. Also, tasks running against these systems should not include any selinux attributes, such as setype or seuser. (Honestly, I haven't tested it fully.) But basic modules like lineinfile or command now work properly.
This does not required disabling selinux; it only prevents Ansible from manipulating selinux attributes. If necessary, you can always use the one of the command modules to script around it.

I would have liked to post this as a comment to the #crankyeldergod's answer (as his response lead me to figure out my fix to this issues) but I don't have enough posts to comment yet.
I also kept receiving the "Aborting, target uses selinux but python bindings (libselinux-python) aren't installed!" error despite having the libselinux-python packages installed. I went into /usr/lib64 and checked the python directories I found there until I located the one with selinux files present. I made note of that version of python and declared it explicitly in my inventory file, ie - ansible_python_interpreter=/usr/bin/python3.6 in my case and that resolved the issue.

Writing gem5 configuration scripts with Pycharm

In order to develop complex gem5 python configuration scripts with more convenient IDE the gem5 lib has to be added
to the project. However, for those who are not experts in python and Pycharm (Such as myself)
there are some difficulties.
For those who are unfamiliar with gem5, this is
a short explanation:
gem5 is an open source simulator that inspects hardware architecture.
It can be downloaded from github: link to github.
The installation process is described at the following link.
<gem5_installation_dir>/gem5/configs/learning_gem5/part1
Inside the above path, there is a basic python script file: simple.py
This file contains some imports.
Editing this file with Pycharm requires some dependencies that are located in the gem5 installation directory.
The questions:
1) How to add those dependencies of gem5 into Pycharm?
2) How to config the Pycharm with gem5 execution command?
Any help would be appreciated.

A few pointers from what I see at gem5 d9cb548d83fa81858599807f54b52e5be35a6b03 (May 2020) under gem5/configs/learning_gem5/part1/two_level.py:
from common: common is at configs/common which gets found because of the above m5.util.addToPath('../../') call, so add configs/ to the PYTHONPATH as shown at: PyCharm and PYTHONPATH
import m5 comes from src/python/m5 so add src/python to the PYTHONPATH as above
from caches import * comes from the sibling learning_gem5/part1/caches.py, so likely this will be found automatically by PyCharm. Otherwise add that directory to the PYTHONPATH.
from m5.objects import *: this is likely the one you are really interested in as it contains all the interesting objects, but unfortunately PyCharm simply cannot handle it I believe since the SimObjects are added dynamically to that namespace at startup in a very convoluted way via PyBind11 native modules + code generation.
A description of how this works in more detail can be found here, but basically every SimObject class goes through some heavy code autogeneration to make this work, say e.g. src/cpu/simple/AtomicSimpleCPU.py due to SimObject('AtomicSimpleCPU.py') in src/cpu/simple/SConscript.
As of 2017, PyCharm said they did not have plans for a proper native C/C++ extension setup: https://intellij-support.jetbrains.com/hc/en-us/community/posts/206018984-Developing-Python-extension-in-C-using-PyCharm
With that said, I've found that it is not worth to use an IDE for the Python part of gem5. This is because the Python tends to be very simple to understand with IPDB (or impossible to setup an IDE for), and if you just grep stuff you tend to quickly guess what is going on. For C++ though I do recommend setting up Eclipse: How to setup Eclipse IDE for gem5 development?
Related: Add custom modules to PyCharm Linter

Python3/MacOSX integration into pycharm

I have had trouble setting up the pycharm ide on my macosx10.7 with python3..
I have scoured every resource available and tried hundreds of approaches, at this point I must accept my incompetence and seek help via this channel.
In my research, I notice a lack of ground-up explanations on python integration into macosx and how to configure pycharm to import modules, run code within the editor, etc. If i ever solve this I will make a very detailed tutorial.
I have imported python3 successfully, it looks like it is linked appropriately from /sys/lib/frameworks to /usr/lib ...etc -- version control is working just fine.
I think my issue is either in setting environmental variables (tried the program to fix this and tried macports) and in the script needed to execute. it will catch errors throughout but final product does not run in python and returns printout of :
/Library/Frameworks/Python.framework/Versions/3.2/bin/python3.2 /Users/anon/Desktop/pythonpractice/Py_Ex/classes.py
Process finished with exit code 0
i really need to get this configuration sound for my python programming class. please help (I've been through every line of pycharm website) .. preferably is there a way to map it via terminal? thanks for anyone who took the time to read this.

Summary of the discussion above:
Python 3.2.2 installation was broken on this Mac, installing ActiveState Python 3.2.2 from scratch and configuring it in PyCharm has fixed the problem.
Python path to be used in PyCharm settings: /Library/Frameworks/Python.framework/Versions/3.2/bin/python3
Incompatible third-party plug-ins may break PyCharm, uninstall/disable them in Preferences | Plugins.
Ensure the latest PyCharm version is installed.
User's code depends on the graphics.py module which was not in the project or in the PYTHONPATH. Putting it into the project has solved the problem.
Most likely the wrong Run/Debug configuration was used in PyCharm, the easiest way to run or debug such scripts is by using the editor context menu Run and Debug actions. PyCharm creates the configuration automatically and debugging works fine as shown of the screenshot:
If one wants to configure and debug it, he can use the code.zip file to get started.
Sorry for the comments mess above, but it was not possible to move it into chat as user had only 1 reputation point, hence not able to use the chat feature of StackOverflow.