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not able to uninstall python and get python 3

i just started using python and i use VS Code.
When i do
python --verion
i get python version 2
py --version
i get python version 3
i wanted to install networkx which turned out to only work with python version 3. I did multiple things to change python version to 3 but could not.
So i decided to uninstall python and went to control panel and uninstalled
python
python launcher
and restarted the computer.
But when i run
python --version
it still shows up python 2.7.18
and this is my where python output
can anyone please help me to understand whats going on and how can i get python 3 to my system.
My solution:
I had already tried putting the python 3.1 path (default added by python when you click add path option while installing) above all path but had no intended outcome.
What i did:
installed python again and this time added the path by myself and moved it to top.
Now when i run
where.exe python it shows me three path, i don't know much but looks like there are two/three python in the system but it started showing python 3 for now.
my where.exe python output:
uninstalled

In windows If you do not have correct environment variable set then this is likely to cause the problem.
On your Powershell if you type $env:path or on command prompt echo %PATH%
you shall see your environment variable path which you have set,
where-in, either you may not have path to directory of Python 3 or you have it appended after Python2.
i.e.:
if your result show up as (... could be other paths in your variable) then only you will get python.exe to be pointing to your Python3 path:
...
C:\Python38\Scripts;C:\Python38;
...
C:\Python27\Scripts;C:\Python27\;
...
Update:
Based on OP comment it looks like there is misunderstanding with how environment variable works.
If you are still looking for why question then follow below steps:
List down all paths which are under environment variable PATH
Now go over each path and check contents of the directory. One of the directory would be having the python which is throwing you the version which you find mystery.

How to resolve "Invalid Python interpreter name 'python.exe'!" error in PyCharm

I'm trying to add my Python interpreter to PyCharm but whenever I navigate to python.exe and click Ok it says Invalid Python interpeter name 'python.exe'! (the spelling mistake for interpeter is how it's spelled in the dialog that appears)
I installed Python through the Microsoft app store. The interpreter is located at ~\AppData\Local\Microsoft\WindowsApps\python.exe. This is the path I navigate to when selecting the interpreter in PyCharm. There are also python3.exe and python3.7.exe but those don't work either. I can run python from the command line and it behaves as expected.

I got the same error message when I imported a project of an existing virtual environment to pyCharm. Though the name and path of the exe was correct, pyCharm did not accept it.
My solution was to remove the Interpreter in pyCharm and to add it again. Then the Error was gone. Perhaps that can help someone ...

The EAP (Early Access Program) build Pavel suggests did not work for me. I hope this gets sorted out in PY-33406 as Pavel suggests.
In the responses for that issue, the thing that worked for me is included. I created a virtual environment using venv and was able to use that python interpreter. As it says on that page...
Open the windows prompt
Go to the project root: cd X:\path\to\project
Type python -m venv venv
Chose "existing interpreter" instead of
creating a new venv using Pycharm and pick the Python binary from the
virtualenv you created in the previous step
Hope that helps, happy to update this to add more detail if not.

Remove the interpreter (by using minus sign) and add it again!

In case anyone else is still facing this issue, reinstalling PyCharm did the trick for me.

If you're adding an already existing virtual environment, it may sound dumb but check that the python executable does exist. If it's a symlink, it should point to a valid location in your system.
In my case, I had overwritten the already existing python executable with a new python executable created by clicking the "new" option in the virtual environment creation by mistake, and the result was an incomplete virtual environment setup in which the python executable was a symlink to a non-existing python executable. Recreating the virtual environment from scratch and using it as an "existing" virtual environment solved the issue.
I know these are basic checks, but hopefully this helps someone out there who rushed for an answer.

Try PyCharm 2019.2 EAP build. The problem should be fixed: https://youtrack.jetbrains.com/issue/PY-33406 (or better use Python from python.org).
I reported the typo to PyCharm's bug tracker, thanks https://youtrack.jetbrains.com/issue/PY-36686

Adding Python 2.7 & 3.x Interpreters to PyCharm

I'm having issues adding a project interpreter to PyCharm from a new Anaconda environment. I have Anaconda2 installed with one Python 2.7 environment (C:\Anaconda2\python.exe) that I've been using on Pycharm without issue for several months.
I am attempting to add a second Python 3.6 interpreter (from C:\Anaconda2\envs\py36\python.exe) to my PyCharm. After adding the Local Interpreter to Pycharm, I run into a MS Visual C++ Runtime Error R6034 "An application has made an attempt to load the C runtime library incorrectly".
From cursory googling, it seems that there could be a runtime DLL conflict (potentially msvcr90.dll) between Python 2 & 3. All fixes I see involve editing the executable path of the application, but I don't think this is feasible for my Pycharm use case. How do I get rid of this error, or just generally be able to use both Python 2 & 3 interpreters through my PyCharm?

I think that's the problem with Anaconda and different msvc dll in the computer.
You can test the conda command in the command line, to see if R6034 happens. If it happens, try the following solution:
I had a similar problem with Anaconda3 and Python27. I solved this problem via executing the following command in cmd, outside of any conda environment:
conda install msvc_runtime
After installing the packages, open a new command and test if the R6034 error still appears.

I had a similar issue and was able to resolve it by selecting:
File --> Invalid Caches / Restart...
from PyCharm's main menu.
You may also want to double check that any Conda Environments that you have defined as Python Interpreters in PyCharm are properly configured per the docs

This issue was absolutely maddening. Million R6034 error windows would just keep popping up one after another if I just wanted to get help on a function. I researched it for months, on/off, opened tickets with JetBrains to no avail.
If you need to have multiple versions of Anaconda, and if you have Anaconda paths in your PATH, before launching PyCharm, delete all Anaconda paths from PATH, and then start PyCharm. You need to create a separate wrapper launcher script for PyCharm to fix PATH before PyCharm is started. Note that alternative of starting PyCharm and then fixing interpreter and python console PATHS inside PyCharm do not really work. Because PyCharm may be using a system path to access python to read documentation etc. So the only clean fix is to fix the system PATH before PyCharm starts.
Once you understand what needs to be done, then you can use your own steps/tools. This worked for me:
Create a script that modifies PATH. I used Python for that, sed or any other tools are fine too. The script simply examines each path element and removes it if it refers to Anaconda, and then puts it back together:
path_cleanup.py:
path_old = os.environ['PATH']
path_python_removed = [loc for loc in path_old.split(pathsep) if not ('python' in loc or 'Ana' in loc)]
print(pathsep.join(path_python_removed))
Create Powershell script to fix PATH and start PyCharm from that clean environment. To find PyCharm path, the simplest is to start it up the usual way, and head to Task Manager, right mouse click on pycharm64.exe process and select "open file location" to get the full path.
pycharm_clean.ps1
$Env:Path=python path_cleanup.py # call the script to fix the PATH
start-process $PYCHARM_PATH\pcharm64.exe -WindowStyle Hidden # enter your full path to pycharm and put it into background.
You can create a shortcut to launch pycharm_clean.ps1 + you can add it to your windows start up folder to be launched upon login: %APPDATA%\Microsoft\Windows\Start Menu\Programs\Startup\
If you use BASH inside Cygwin, then steps for path clean up require a bit more tuning, but nothing you cannot do. If you need help, put a comment and I can add that script as well.

python not recognized in Windows CMD even after adding to PATH

I'm trying to -learn to write and- run Python scripts on my Windows 7 64 bit machine. I installed Python in C:/Python34, and I added this to my Windows' PATH variable :
C:\Python34; C:\Python34\python.exe
(the second one is probably meaningless but I tried) and still I get this error in Windows command line :
C:\Users\me>python test.py
'python' is not recognized as an internal or external command,
operable program or batch file.
So how do I truly install Python on my Windows x64 machine ?

This might be trivial, but have you tried closing your command line window and opening a new one? This is supposed to reload all the environment variables.
Try typing
echo %PATH%
into the command prompt and see if you can find your Python directory there.
Also, the second part of your addition to the PATH environment variable is indeed unnecessary.

I had the same problem: python not being recognized, with python in the path which was was not truncated.
Following the comment of eryksun in yossim's answer:
Also, if you installed for all users you should have %SystemRoot%\py.exe, which >is typically C:\Windows\py.exe. So without setting Python's directory in PATH >you can simply run py to start Python; if 2.x is installed use py -3 since >Python 2 is the default. – eryksun
I tried to use py instead of python and it worked.
Meaning:
python setup.py build -> does NOT work.
py setup.py build -> does work.
Hope it helps

I was also having the same problem.
Turns out the path I added included '..\python.exe' at the end, which as turns out was not required. I only needed to add the directory in which 'python.exe' is in (which in my case is the Anaconda's distribution directory in Users folder), similar to what we do when installing JDK in our system's PATH variable.
Hope it helps!

It wasn't working for me even after adding the path. What finally did the trick, was changing the order of listed paths in the PATH variable. I moved %USERPROFILE%\AppData\Local\Microsoft\WindowsApps down vs. having it the first path listed there.

Environment PATH Length Limitation is 1024 characters
If restarting your cmd window does not work you might have reached the character limit for PATH, which is a surprisingly short 1024 characters.
Note that the user interface will happily allows you to define a PATH that is way longer than 1024, and will just truncate anything longer than this. Use
echo %PATH%
in your cmd window to see if the PATH being truncated.
Solution
Unfortunately, there is no good way to fix this besides removing something else from your PATH.
NOTE: Your PATH = SYSTEM_PATH + USER_PATH, so you need to make sure the combined is < 1024.

I did everything:
Added Python to PATH
Uninstall all the Pythons - Both from downloaded python.org and Microsoft Store and reinstall from python.org
Change the order of PATH
Deleted %USERPROFILE%\AppData\Local\Microsoft\WindowsApps from PATH
But nothing worked. What worked for me was:
Settings > Application > App execution aliases. Then disable all the Pyhtons from here and it worked!

Also, make sure to leave no spaces after the semi-colon.
For example, this didn't work for me:
C:\Windows\system32; C:\Python27; C:\Python27\Scripts;
But, this did:
C:\Windows\system32;C:\Python27;C:\Python27\Scripts;

I'm late to the game here, but I'd like to share my solution for future users. The previous answers were on the right track, but if you do not open the CMD as an administrator, then you will be thrown that same error. I know this seems trivial and obvious, but after spending the past 8 hours programming before attempting to install Django for the first time, you might be surprised at the stupid mistakes you might make.

I have faced same problem even though my path contains 400 characters.
Try to update the path from the command line(Run as administrator)
Command to update path: setx path "%path%;c:\examplePath"
After this command I could see that paths that I configured earlier in environment variables got updated and working.
To check the configured paths: echo %PATH%

I was facing similar porblem. What helped me is where command.
C:\WINDOWS\system32>where python
C:\Users\xxxxxxx\AppData\Local\Microsoft\WindowsApps\python.exe
C:\Program Files (x86)\Microsoft Visual
Studio\Shared\Python39_86\python.exe
On updating PATH variable to point to only one desired directory (basically I removed %USERPROFILE%\AppData\Local\Microsoft\WindowsApps from PATH) fixed my problem.

I had the same issue with Python 2.7 on Windows 10 until I changed the file path in Enviroment Variables to the folder path, ie C:\Python27\python.exe didn't work but C:\Python27\ did work.

For me, installing the 'Windows x86-64 executable installer' from the official python portal did the trick.
Python interpreter was not initially recognized, while i had installed 32 bit python.
Uninstalled python 32 bit and installed 64 bit.
So, if you are on a x-64 processor, install 64bit python.

I tried it multiple times with the default installer option, the first one, (Python 3.7.3) with both 'add to environment variable' and 'all users' checked, though the latter was greyed out and couldn't be unchecked.
It failed to work for other users except for the user I installed it under until I uninstalled it and chose "Custom Install". It then clearly showed the install path being in the C:\Program Files\Python37 directory when it was failing to install it there the other way even though the 'All Users' option was checked.

Same thing was happening with me when i was trying to open the python immediately with CMD.
Then I kept my in sleep mode and started CMD using these Key Windows_key+R, typed cmd and OK. Then the package of python worked perfectly.

Uninstall python and pyqt
Then go to pyqt setup and open installation but don't install. You will see a message box saying something like pyqt version built with python version 32bit/64bit.
Then see python version bit and download that version from python.org from all release menu.
Then first install python and then install pyqt. It will work like butter.

I spent sometime checking and rechecking the path and restarting to no avail.
The only thing that worked for me was to rename the executable C:\Python34\python.exe to C:\Python34\python34.exe. This way, calling typing python34 at the command line now works.
On windows it seems that when calling 'python', the system finds C:\Python27 in the path before it finds C:\Python34
I'm not sure if this is the right way to do this, seems like a hack, but it seems to work OK.

How to integrate Django and Cygwin?

I have a Windows box with cygwin, python and django installed.
Now I want to run django-admin, but when I do I get the error:
$ django-admin.py
c:\Python26\python.exe: can't open file '/usr/bin/django-admin.py': [Errno 2] No such file or directory

From here
For Windows users, who do not have symlinking functionality available, you can copy django-admin.py to a location on your existing path or edit the PATH settings (under Settings - Control Panel - System - Advanced - Environment...) to point to its installed location.
hope this helps

I just ran into the exact same problem. I've found that if you already have the windows version of python installed, it seems to get priority over the cygwin version. I solved the problem by editing /etc/profile and changed:
PATH=/usr/local/bin:/usr/bin:/bin:/usr/X11R6/bin:$PATH
...to:
PATH=/usr/local/bin:/usr/bin:/bin:/usr/X11R6/bin:
...which I think stops cygwin from adding the normal windows path. Once you've got that working, download django into some directory, move into that directory and type:
python setup.py install
I was having problems to begin with because I had omitted the 'python' bit at the start

As for the step on how to start your django in cygwin
first open your windows command prompt
then register the python environment by doing this:
Path %path%;C:\Python27;C:\Python27\Scripts
then now go to the installation folder of your cygwin
cd C:\cygwin
then run the cygwin.bat like this:
C:\cygwin>cygwin.bat <enter>
then cygwin will open, and type python to see if it now working
$ python
Voila we are done!

Sort of sounds like the windows version of Python is trying to run instead of the cygwin one. What happens if you type this:
$ python django-admin.py
Here I'm assuming
$ which python
Finds the cygwin version of python (which will be something like /usr/bin/python).
You may also try (temporarily) uninstalling the windows version of python and use only cygwin.

Help us help you. Is there a reason why you are running the windows python interpreter (c:\Python26\python.exe) as oppose to the cygwin python interpreter (/usr/bin/python.exe)? That could be your problem. So to troubleshoot that, you might consider removing the windows native interpreter or simply making sure the cygwin path is listed before the c:\Python26 path in the windows global PATH variable.

Add the location of your django/bin folder (or wherever else you keep django-admin.py) to your PYTHONPATH environment variable.

Like Brian mentioned you are running the Windows version of Python which won't work with the Cygwin installation.
A word of warning. When I first started using Django, I tried installing it in Cygwin and had a variety of problems and ended up switching to the regular Windows version of Python. Unfortunately, I didn't document all my issues, but I remember some of them had to do with the database libraries. Anyway, that was a few months ago when I knew less about Django than I do now. Maybe the problems I ran into have been solved and perhaps now that I know more I could get it to work, but running Django on Cygwin does seem to be the road less traveled. Good luck. :)

Just copy the django-admin.py to the current location you are working on for e.g
on Cygwin:
<root>/projects/
on your windows directory it will look like this:
C:\cygwin\home\<your computer name>\projects\
once you copy the file, you can create your project by typing this command:
$ python django-admin.py startproject mysite
and that's all - you have completed your first project using the Cygwin linux-like environment.

Add two lines to .bash_profile and .bashrc files (view their difference here). You can find them in C:\cygwin\home\[username]:
export PATH=$PATH:/cygdrive/c/python2.7
export PYTHONPATH=$PYTHONPATH:/cygdrive/c/python2.7/Lib/site-packages
Hope this helps