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any known way to create a device-to-device portable self-contained python runtime?

I want to distribute a python program on, say, Windows and/or Mac, but I don't want to give the user the headache of ensuring there is an appropriate python runtime installed on their machine. And i don't want to interfere with their machine's configuration by, let's say, requesting root privileges and installing a system-wide python runtime on their system that suits my program specifically because it's too invasive and might cause compatibility collisions with other installed versions of the runtime.
I would much rather have a self-contained executable that could be, for example, stored on a USB flash-drive, inserted into the system, and then maybe with a stepping-stone binary executable that just invokes the device-portable runtime on a python script that I provide, I could then run the program as if it were a self-contained binary executable (with only standard-library dependencies).
A link to this binary executable could be published into main-menu program lists, docks, or desktops. And it could be invoked by shell scripts or other executed-by-proxy mechanisms. Such a no-install/self-contained python program could potentially be a first-class user-invokable application. This is what I want to achieve.
I googled around for projects that provided a device-portable/mobile python installation and so far I've only found portablepython.com. Unfortunately it says the project is discontinued and no download link for the project is provided. it listed some similar projects but they all seemed defunkt or with a very different focus.
Does anyone know of an active project that is or includes such an independent/portable/mobile/no-install distribution for python?
or is there some way i could configure python's build system to build a noinstall-friendly product?
any ideas welcome. thanks for your input!

After more searching I found that Python.org publishes its own standalone-python distribution called the embeddable zip file.
This is exactly what I was searching for. It's a basic python standalone runtime that requires relatively few megabytes of storage.
I started with this embeddable distro and then cajoled a standalone copy of pip to work with it. Problem solved.

Improving upon #oreus2020's answer, you can download the embeddable zip file from here. Then, unzip the compressed file to a folder of your choice. Go to the root of your install and find python._pth file and open it in a text editor. Remove the "#" before import site(This file is the one which manages the environment of the portable install. If you want anything to be recognized by the portable python interpreter, just throw the path in here and that's it!). If you want pip, go to this page and save it in the root of your portable install and run it using the portable python interpreter like ./python get-pip.py from a commandline opened at the root of your install. Pip installed! To use the pip, do ./python -m pip <commands> from the commandline opened at the root of your install and then open the python._pth file and insert the following below the "." ./Lib/site-packages ./Scripts. Voila, you got yourself a python portable install!
My python._pth file looks like:
python39.zip
.
# Uncomment to run site.main() automatically
./Repo
./Repo/Code
./Repo/Code/cogs
./Lib/site-packages
./Scripts
import site
If you are still wondering, here is the link to the one I made for myself.
P.S. Pardon my bad English

Changes in Python scripts are not accepted

I'm new to Python, so I think my question is very fundamental and is asked a few times before but I cannot really find something (maybe because I do not really know how to search for that problem).
I installed a module in Python (reportlab). Now I wanted to modify a python script in that module but it seems that the python interpreter does not notice the updates in the script. Ironically the import is successful although Python actually should not find that package because I deleted it before. Does Python uses something like a Cache or any other storage for the modules? How can I edit modules and use those updated scripts?

From what you are saying, you downloaded a package and installed it using either a local pip or setup.py. When you do so, it copies all the files into your python package directory. So after an install, you can delete the source folder because python is not looking here.
If you want to be able to modify, edit, something and see changes, you have to install it in editable mode. Inside the main folder do:
python setup.py develop
or
pip install -e .
This will create a symbolic link to you python package repository. You will be able to modify sources.
Careful for the changes to be effective, you have to restart your python interpreter. You cannot just import again the module or whatever else.

Python compile all modules into a single python file

I am writing a program in python to be sent to other people, who are running the same python version, however these some 3rd party modules that need to be installed to use it.
Is there a way to compile into a .pyc (I only say pyc because its a python compiled file) that has the all the dependant modules inside it as well?
So they can run the programme without needing to install the modules separately?
Edit:
Sorry if it wasnt clear, but I am aware of things such as cx_freeze etc but what im trying to is just a single python file.
So they can just type "python myapp.py" and then it will run. No installation of anything. As if all the module codes are in my .py file.

If you are on python 2.3 or later and your dependencies are pure python:
If you don't want to go the setuptools or distutiles routes, you can provide a zip file with the pycs for your code and all of its dependencies. You will have to do a little work to make any complex pathing inside the zip file available (if the dependencies are just lying around at the root of the zip this is not necessary. Then just add the zip location to your path and it should work just as if the dependencies files has been installed.
If your dependencies include .pyds or other binary dependencies you'll probably have to fall back on distutils.

You can simply include .pyc files for the libraries required, but no - .pyc cannot work as a container for multiple files (unless you will collect all the source into one .py file and then compile it).

It sounds like what you're after is the ability for your end users to run one command, e.g. install my_custom_package_and_all_required_dependencies, and have it assemble everything it needs.
This is a perfect use case for distutils, with which you can make manifests for your own code that link out to external dependencies. If your 3rd party modules are available publicly in a standard format (they should be, and if they're not, it's pretty easy to package them yourself), then this approach has the benefit of allowing you to very easily change what versions of 3rd party libraries your code runs against (see this section of the above linked doc). If you're dead set on packaging others' code with your own, you can always include the required files in the .egg you create with distutils.

Two options:
build a package that will install the dependencies for them (I don't recommend this if the only dependencies are python packages that are installed with pip)
Use virtual environments. You use an existing python on their system but python modules are installed into the virtualenv.
or I suppose you could just punt, and create a shell script that installs them, and tell them to run it once before they run your stuff.

python - web2py - can't seem to find lxml - ActivePython - windows7

Have been using ActivePython on windows7 and lxml seems working without an issue..
There were a lot of other third party packages I had & they were working too..
Until I wanted to use it inside Web2Py.
All the others seem to be working if I copy them directly inside c:/web2py/applications/myApp/modules
With lxml, seems I need to copy something else..
I have a third party module, which imports lxml like this : from lxml.etree import tostring
It ends up throwing - No module named lxml.etree
My test program outside web2py runs without an issue with both these modules.
When I do a pypm files lxml I see this :
%APPDATA%\Python\Python27\site-packages\lxml-2.3-py2.7.egg-info
What else should I copy along with the lxml directory into the modules directory ?
Pretty sure it's me doing something wrong instead of Web2py, but can't put a finger on..
web2py version = Version 1.99.7 (2012-03-04 22:12:08) stable

If you are using the Windows binary version of web2py, it comes with its own Python 2.5 interpreter and is self-contained, so it won't use your system's Python 2.7 nor see any of its modules. Instead, you should switch to running web2py from source. It's just as easy as the binary version -- just download the zip file and unzip it. You can then import lxml without moving anything to the application's /modules folder.

Python 2.4 OAuth compatibilty

I have installed python oauth on my python2.4 platform, however making the python twitter package work requires some tweaks in oauth.. I am quite new to python but I assume I cannot alter the egg.. how do I install a non-egg version and how do I remove the egg safely ?

Python eggs (like java jar files) use the zip format. So to answer your question on how to make your tweaks:
Find the file location
Navigate to location, make a backup copy
If the file is stored as oauth.egg, unzip it
Start modifying!
Find the egg location
Open up a python interpreter and run the following:
>>> import oauth
>>> oauth.__file__
'/usr/lib/python2.6/dist-packages/oauth/__init__.pyc'
Your path will differ, but that will tell you where to look. Often the source code will be unpacked and available in the same directory as a .py file, in this case oauth.py.
(By the way the __file__ attribute is available on all modules unless they represent linked C libraries, but that should not be your case with oauth.)
I'll skip the file navigation, backup, and unzip details, as those will depend on your system.
Removing a Python Egg Safely
I'm afraid my knowledge is lacking here. Removing the egg file is easy, but I'm not at all sure how to check for dependencies from other packages, other than running $ ack python.module.to.remove across your python library. But some basic facts that may help
Directories that include __init__.py in them are treated as part of the python path. See Modules and Packages
Python eggs will add a .pth file containing additional places to add to the path.
>>> import sys; sys.path will show every directory that Python searches for modules/packages.
The PYTHONPATH environment variable can be configured to add paths you choose to the python search path
PS If you are new to Python, I highly recommend finding out more about IPython. It makes the Python intepreter much nicer to deal with.
Good luck and welcome to Python!