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pyinstaller: popen doesn't run after producing exe

I compiled my python application using pyinstaller and the exe works fine, but when I run it on a different machine without python any part of the code which contains subprocess.Popen()doesn't run.
I read too many questions but I couldn't wrap my head around this.
My popen line:
try:
process = subprocess.Popen(['python', os.path.abspath('about.py')],stdout=subprocess.PIPE,stderr=subprocess.PIPE,stdin=subprocess.PIPE,
shell=True)
except Exception as e:
print(e)
Note that the executable runs on the host machine, but on another machines it runs but fails when launching the popen.
===UPDATE====
The console shows nothing and doesn't print an exception, so I guess this is a problem with python not being found. How can I fix this?
===UPDATE2====
Following the suggestion of viilpe I used "exec(open..." but it required me to import the about.py module first; importing the module runs it on top of the main module.
Putting exec(open...) inside the try\except runs the main module and the about module alongside each other; ruining the application's GUI.
I'm using "kivy" as my GUI library.

Looks like you want to execute about.py but there is no python.exe in pyinstaller bundle.
As advised here you can do it this way:
exec(open('about.py').read())

The whole point of PyInstaller is to make the destination computer be able to run your script without having a standalone python installation. You can't run a subprocess on a tool which isn't (necessarily) installed.
There are various ways to run Python as a subprocess of itself natively; start by exploring the multiprocessing library.
If the requirement to run Python twice is not a hard one, the absolutely simplest solution is to import about and run the code as part of your script. This probably requires some refactoring of the code in about.py.

CPU occupation while using python subprocess module

I wrote a c++ program a.out and tried to run the program by using subprocess module in python, called run.py. After running the script, I used top to check cpu usage and found that the run.py does not shown in the list while a.out is running.
What happened to run.py? Where is it?

It is sleeping waiting for your C++ program to exit. That is because you used subprocess.call.
You can use subprocess.Popen which doesn't wait unless you call its wait method if you need your Python program to continue doing something else while the program runs.

python subprocess console output - eclipse calls batch calls python calls exe

I have the situation that I want the job done from eclipse so I use eclipse's .launch configuration. I tried to make it run python directly but got error: error 193 (%1 is not a valid Win32 app). where %1 is probably my python script.
I decided to create a simple batch script that calls this big wild python animal.
I did a lot of combinations and found this the best (batch outputs some strings, runs python, waits for it, the outputs some strings again):
start /b /wait "Python_script.py" "%1" "%2" "%3" "%4" "%5"
It worked until python itself started to run exe file.
Once again I tried a lot of combinations:
os.system([exe, arg1, arg2, ...]) and
subprocess.call(..) and subprocess.check_output(..)
-> I either didn't see the output in eclipse console, or the output was delayed or there was only python / or only exe's output in console.
finally I used subprocess.Popen(...) and it's nearly allright - the only defect is that the output from python script don't wait for exe's process to finish, and when I use subprocess.Popen(...).wait() exe passes output to console but the WHOLE output from python script is delayed until the 'exe' terminates. I want to delay only the part of pythons script output that is written after the exe is called.
how to achieve this 'partly console output delay' is the main topic
advices on python and eclipse .launch configuration will be appreciated
general advices on how does the communication between this processes(?) work will be appreciated
Thanks!

It sounds to me like you have three different processes you're trying to get to work together, you've tried a whole bunch of stuff to get it working, and the code is complex enough that you can't easily post it here. That makes it pretty hard to get a good answer (Stack Overflow works much better with focused questions), but here's the general approach I'd take:
Does your script run if you try to run Python_script.py directly from the command prompt?
If it doesn't, then look into registering the .py file type in Windows.
If it does, then maybe Eclipse launch configurations don't support or don't properly support Windows registered file types. There should be no need to mess with batch files and start; just replace Python_script.py in your launch configuration with c:\Python27\python.exe Python_script.py (or similar).
Get your script working from a command prompt - able to run, with proper Python and subprocess output, and waiting for everything to terminate.
If things work from the command prompt and still don't work from Eclipse, then post a new question with a small snippet of code showing what you're trying and a description of what's wrong. subprocess.call, subprocess.check_output, and Popen all have different uses, so it's hard to give general advice besides just referring to the documentation.

launch external shell python instance in shell from python

I'd like to call a separate non-child python program from a python script and have it run externally in a new shell instance. The original python script doesn't need to be aware of the instance it launches, it shouldn't block when the launched process is running and shouldn't care if it dies. This is what I have tried which returns no error but seems to do nothing...
import subprocess
python_path = '/usr/bin/python'
args = [python_path, '&']
p = subprocess.Popen(args, shell=True)
What should I be doing differently
EDIT
The reason for doing this is I have an application with a built in version of python, I have written some python tools that should be run separately alongside this application but there is no assurance that the user will have python installed on their system outside the application with the builtin version I'm using. Because of this I can get the python binary path from the built in version programatically and I'd like to launch an external version of the built in python. This eliminates the need for the user to install python themselves. So in essence I need a simple way to call an external python script using my current running version of python programatically.
I don't need to catch any output into the original program, in fact once launched I'd like it to have nothing to do with the original program
EDIT 2
So it seems that my original question was very unclear so here are more details, I think I was trying to over simplify the question:
I'm running OSX but the code should also work on windows machines.
The main application that has a built in version of CPython is a compiled c++ application that ships with a python framework that it uses at runtime. You can launch the embedded version of this version of python by doing this in a Terminal window on OSX
/my_main_app/Contents/Frameworks/Python.framework/Versions/2.7/bin/python
From my main application I'd like to be able to run a command in the version of python embedded in the main app that launches an external copy of a python script using the above python version just like I would if I did the following command in a Terminal window. The new launched orphan process should have its own Terminal window so the user can interact with it.
/my_main_app/Contents/Frameworks/Python.framework/Versions/2.7/bin/python my_python_script
I would like the child python instance not to block the main application and I'd like it to have its own terminal window so the user can interact with it. The main application doesn't need to be aware of the child once its launched in any way. The only reason I would do this is to automate launching an external application using a Terminal for the user

If you're trying to launch a new terminal window to run a new Python in (which isn't what your question asks for, but from a comment it sounds like it's what you actually want):
You can't. At least not in a general-purpose, cross-platform way.
Python is just a command-line program that runs with whatever stdin/stdout/stderr it's given. If those happen to be from a terminal, then it's running in a terminal. It doesn't know anything about the terminal beyond that.
If you need to do this for some specific platform and some specific terminal program—e.g., Terminal.app on OS X, iTerm on OS X, the "DOS prompt" on Windows, gnome-terminal on any X11 system, etc.—that's generally doable, but the way to do it is by launching or scripting the terminal program and telling it to open a new window and run Python in that window. And, needless to say, they all have completely different ways of doing that.
And even then, it's not going to be possible in all cases. For example, if you ssh in to a remote machine and run Python on that machine, there is no way it can reach back to your machine and open a new terminal window.
On most platforms that have multiple possible terminals, you can write some heuristic code that figures out which terminal you're currently running under by just walking os.getppid() until you find something that looks like a terminal you know how to deal with (and if you get to init/launchd/etc. without finding one, then you weren't running in a terminal).

The problem is that you're running Python with the argument &. Python has no idea what to do with that. It's like typing this at the shell:
/usr/bin/python '&'
In fact, if you pay attention, you're almost certainly getting something like this through your stderr:
python: can't open file '&': [Errno 2] No such file or directory
… which is exactly what you'd get from doing the equivalent at the shell.
What you presumably wanted was the equivalent of this shell command:
/usr/bin/python &
But the & there isn't an argument at all, it's part of sh syntax. The subprocess module doesn't know anything about sh syntax, and you're telling it not to use a shell, so there's nobody to interpret that &.
You could tell subprocess to use a shell, so it can do this for you:
cmdline = '{} &'.format(python_path)
p = subprocess.Popen(cmdline, shell=True)
But really, there's no good reason to. Just opening a subprocess and not calling communicate or wait on it already effectively "puts it in the background", just like & does on the shell. So:
args = [python_path]
p = subprocess.Popen(args)
This will start a new Python interpreter that sits there running in the background, trying to use the same stdin/stdout/stderr as your parent. I'm not sure why you want that, but it's the same thing that using & in the shell would have done.

Actually I think there might be a solution to your problem, I found a useful solution at another question here.
This way subprocess.popen starts a new python shell instance and runs the second script from there. It worked perfectly for me on Windows 10.

You can try using screen command
with this command a new shell instance created and the current instance runs in the background.
# screen; python script1.py
After running above command, a new shell prompt will be seen where we can run another script and script1.py will be running in the background.
Hope it helps.

subprocess running python getting import error

I'm trying to run a python script from a python program by kicking it off from subprocess (The reason is that the main program has to have exited when the script runs, with a combination of wx.CallAfter and Close). However when the script runs I get an error on line 1 with ImportError: No module named os which makes me think it's something to do with the PythonPath, but I can run the script just fine from a terminal.
Why can't the script see any core modules when run this way?
Edit:
The line in question is:
wx.CallAfter(subprocess.Popen,'python %s "%s" %s %s'%(os.path.join(BASE_DIR,"updatecopy.py"),BASE_DIR,pos[0],pos[1]),shell=True)
BASE_DIR is just the directory that the script lives in.

subprocess is there because os.exec* has been deprecated so I wouldn't suggest using that in place of Popen as someone suggested.
I've seen this issue crop up when running from a frozen process. If that is the case then you're most likely inheriting a weird environment for the new python process.
Most frozen scripts will be trying to run from a zip file, in which case it's no wonder that Python can't find anything, it's all trapped in a zip file :)
If this is the situation then try running using the python executable that you are using to run the frozen script. It should be able to deal with the special environment.

Maybe you could use os.execv instead of Popen.
From os/python docs:
These functions all execute a new program, replacing the current process; they do not return. On Unix, the new executable is loaded into the current process, and will have the same process id as the caller. Errors will be reported as OSError exceptions.
(emphasis mine)