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C++ python module linking on MacOS

I'm building a C++ python module on MacOS.
On my machine I have python, installed in directory /Library/Frameworks/Python.framework/Versions/3.9. I'm specifing python includes directory as -I/Library/Frameworks/Python.framework/Versions/3.9/Headers and libraries directory as -L/Library/Frameworks/Python.framework/Versions/3.9/lib -lpython3.9.
So it builds good and runs good on my machine and other machines, where python is installed into /Library/Frameworks/Python.framework/Versions/3.9.
But when I move my library to machine, where python is installed into another folder, like /usr/local/Cellar/python#3.9/3.9.12/Frameworks/Python.framework/Versions/3.9, I'm getting import module error.
otool -L _mymodule.so command returns hardcoded absolute path to /Library/Frameworks/Python.framework/Versions/3.9. I know, that I can change the path using install_name_tool, but I don't want to ask and explain my module users to do that, as well as to make a symlink.
How can I make module more portable and python install path independent?

Modules Not Found - I cannot externally run a .py file developed using PyCharm

I am using PyCharm to develop a python project, which uses an external library called win10toast. I have installed win10toast using PyCharm. However, when I tried to run the .py file using cmd (i.e Externally running the python file), an error shows up:
ModuleNotFoundError: No module named 'win10toast'.
I have python 3.6.4. I installed win10toast using PyCharm.
from win10toast import ToastNotifier
I expect the program to run without any error, but currently I am getting the ModuleNotFound error.

Python can be tricky to run properly because it is sensitive to where you installed your dependencies (such as external libraries and packages). If you installed Python to one directory, but accidentally installed the external library to another directory, when you run your .py program, it will be unable to call from the external library because it doesn't exist in the same library that Python is running from.
Lookup where you installed Python on your computer and then find where you installed the external library. Once your find where you installed the external library, move its entire package content to the same directory where Python is installed. Or better yet, reinstall the external library with pip into the same directory as Python.
If you're on Mac, Python and its related dependencies are usually stored somewhere in /User/bin. If you're on Windows, it will be stored somewhere in your C:// directory (possibly somewhere in C:\Users\username\Local\AppData). If you're on Linux, it will be stored somewhere in /usr/bin. Whatever you do, don't move Python from wherever it is because sometimes that can mess up your system for certain operating systems like Mac, which comes with its own version of Python (Python 2.7 I believe, which is outdated anyway).
Lastly, you may have two different versions of Python on your computer, which is common; Python 2.7 and Python 3+. If you wrote your program in one version, but ran it from the other, the external library can only be called from whichever Python version you installed it to. Try running your .py program with python3 instead of python (or vice versa) and see what happens. If it works with one python version over the other, that tells you that the external library is installed in the other version's directory.
That should solve your issue.

I would suggest that you not use PyCharm to install packages, at least not
if the result deviates in the slightest from doing a "pip install" at the command line. I see no reason to involve PyCharm in configuring Python installations. It's just asking for trouble.
I admit that I'm not familiar with the practice I'm suggesting you avoid. I've been using PyCharm since pretty much the week it came out (was an avid user of the IntelliJ Python plugin before that), and have never once considered doing anything but installing Python modules at the command line. That way, I'm sure right where those modules are going (into which base Python install or venv). Also, I know I'm doing all that I can to minimize the differences that I might see between running code in PyCharm and running it at the command line. I'm making my suggestion based solely on this practice having never gone wrong for me.
I have multiple base Python versions installed, and dozens of venvs defined on top of those. PyCharm is great at allowing me to indicate which of these I want to apply to any project or Run/Debug configuration, and utilizing them seamlessly. But agin, I administer these environments at the command line exclusively.
I still experience issues in switching between the command line and PyCharm in terms of one module referencing others in a single source tree. My company has come up with a simple solution to this that insures that all of our Python scripts still run when moving away from PyCharm and its logic for maintaining the Python Path within a project. I've explained the mechanism before on S.O. I'd be happy to find that if anyone is interested.

The library win10toast installed in the directory: YOUR_PYCHARM_WORKSPACE\PycharmProjects\YOUR_PROJECT_NAME\venv\Lib\site-packages
but when you are running your program using cmd, pycharm interpreter uses site-packages directory that you installed python at there. for Ex: C:\Python27\Lib\site-packages
So, you can install the win10toast library to this windows directory using pip.

Run a python script in an environment where a library may not be present

I have a python script where I am including a third party library:
from docx import Document.
Now, I need to run this script in an environment where bare-bones python is present but not this library.
Installing this library in the target environment is beyond my scope and I tried using distutils, but couldn't go far with it. The target environment just need to run the script, not install a package.
I am from Java background and in Java I would have just exported and created a jar file which would have included all the libraries I needed. I need to do similar with python.
Edit: With distutils, I tried creating a setup.py:
from distutils.core import setup
import docx
setup(name='mymodule',
version='1.0',
py_modules=['mymodule', docx]
)
But I am not sure this works.

PyInstaller won't work if you can't make a pyc file and you cannot make pyc file unless your code runs without fatal errors.
You could have the import in a try block that excepts ImportError 's but that will result in NameError 's where the package is referenced. Long story short if the package is integral to the script no amount of avoiding it will fix your problem. You need the dependencies.
You said installing the package is beyond your scope, well then, it is time to expand your scope. Docx is an open source package you can find on github here
You can download that and run setup.py

You can include the modules for docx in your application. Just distribute them together.
But docx depends on the lmxl operating system package and needs to run setup on that. You can't just copy it to the target machine.
I'm not sure PyInstaller supports docx, especially add it has the non python dependency.
Really using pip or easy_install is the way to go.

PyInstaller is a program that converts (packages) Python programs into stand-alone executables, under Windows, Linux, Mac OS X, Solaris and AIX.

Bundling win32lfn extension with Mercurial

I'm working on a Windows server application which uses Mercurial for folder synchronisation between servers (so that we only copy the changes each time). The installer includes a bundled hg folder including all the dlls etc for running Mercurial. This currently works well, however users have been reporting error with files with long paths.
There is an win32lfn extension which deals with this issue. I would like to add this to the Mercurial bundle in the installer.
If I copy the win32lfn.py file into the hg folder and add the relevent line to Mercurial.ini then run hg.eze, I get the message:
win32lfn: This extension requires the pywin32 extension
If I attempt to install Python for Windows Extensions (http://sourceforge.net/projects/pywin32/), the installer tells me I need to install Python 2.7 first. I can do this and get it working on my computer, however, I need to bundle this with my installer without requiring the user to install Python.
Mercurial comes with a Python bundled - how can I add the Python for Windows Extensions to this bundle? I have tried copying the dlls into the hg folder without success.
Can anyone direct me to a solution?

This is pretty fortuitous, I just made a commit to win32lfn removing the pywin32 dependency.

Python fails after deleting site.py

tl;dr
I accidentally deleted my Python installation’s site.py file. Now, when trying to start Python, it complains,
ImportError: Couldn't find the real 'site' module
I tried downloading a site.py from setuptools but this results in an infinite recursion in the __boot method around the statement imp.load_module('site',stream,path,descr) (line 37).
Is there a way to fix this without reinstalling Python? What is the site.py file supposed to do?
Some background information:
This is on a Linux server with a custom Python installation in my home directory (~/nfs, to be precise). There are other Python installations on the server (not mine – it’s a mess!) but $PATH and $PYTHONPATH are set up in such a way as to find my installation first.
As to why I deleted the site.py file: I tried executing a setuptools setup.py script and the script told me to delete the file because it “was not created by setuptools”. I foolishly complied.
I suspect that this original error message was caused by the fact that the setuptools implementation is not mine.

The site module sets up your python module search path and some other things. It is somewhat crucial to the normal operation of python.
You can download a new copy from the python source repository:
For python 2.7
For python 3.2
For other python versions, generally the URL is http://hg.python.org/cpython/file/*major*.*minor*/Lib/site.py for the correct tagged version, then select the raw link in the left-hand menu.
If you installed python from a linux distribution package on Ubuntu or Debian, then this file has been customized and you'll need to re-install the appropriate python-minimal package.