Develop Reference

Unable to change Python 2.7 to Python 3.8 on Sublime and VS code

I have been trying to change my python interpreter on sublime text and VS code and no matter what I do, both of them refuse to change. It always picks the default Python 2.7 version.
On sublime, I tried to create a new build tool, added the path to Python3 but nothing is working.
And on, VS code, even if I select Python3 from the drop-down menu, it doesn't change anything.

I changed the system's default python interpreter from 2.7 to 3.9 and set the path on bash profile. It fixed the issue for me.

I don't know about Sublime, but for VS Code, there looks to be quite a few things to verify:
Check your User Settings on whether you've set up a default interpreter for your applications
Are you using Window 10 WSL? Then you might want to check out issue 3227 for vscode-remote-release where the comment was:
So I was having this same exact issue until I read this article on a wsl tutorial. In there it says we should have "Remote - WSL" extension installed (already did). In the bottom left corner "Remote - WSL" installs a status button that has the "greater than" and "less than" symbols displayed. If you click that button and tell VSCode to open up in the remote WSL distro environment it fixed my issue where vscode was unable to find an interpreter for python.

For Sublime, you need to hit ⌘B with your script pane focused in order to use your new python3.sublime-build build system.
It looks like you are running your script within Terminus, which is fine, but you need to use the python3 command when running it from the command line, even if that command line is within Sublime.
Please check out my answer here on how to make a Python build system that accepts user input, as the Sublime "console" doesn't allow you to interact with your program. Since you already have Terminus installed, I'd recommend going down to the bottom of the answer and using the Terminus build system. That way, you won't have to deal with Terminal windows opening every time you run a build.

The terminal window uses your PATH, not the IDE settings, so manually typing out python --version isn't testing anything except the PATH variable
In order for the terminal to use the "correct" python binary you've specified, it would need to give the absolute path to it, which I believe using Command+B (using the build options) in Sublime would do. Similarly, you can use the Run/Debug Configurations in VSCode.
Or you can modify your ~/.zshrc to fix your PATH, for example installing pyenv to change the entire system Python version, or the one for the current folder

Django manage.py [duplicate]

Today when I tried to run simple code on Sublime Text 3, the following message appeared:
Python was not found but can be installed from the Microsoft Store: https://go.microsoft.com/fwlink?linkID=2082640
And when I type Python in CMD, it opens the Windows Store for me to download Python 3.7. This problem started today for no good reason. I didn't change or download anything about Python and already tried reinstalling Python, and the Path environment variable is correct.

Use the Windows search bar to find "Manage app execution aliases". There should be two aliases for Python. Unselect them, and this will allow the usual Python aliases "python" and "python3". See the image below.
I think we have this problem when installing Python because in a new Windows installation the aliases are in the ON position as in image below. When turned on, Windows puts an empty or fake file named python.exe and python3.exe in the directory named %USERPROFILE%\AppData\Local\Microsoft\WindowsApps. This is the alias.
Then Microsoft put that directory at the top of the list in the "Path" environment variables.
When you enter "python" in cmd, it searches the directories listed in your "Path" environment variables page from top to bottom. So if you installed Python after a new Windows 10 install then get redirected to the Windows Store, it's because there are two python.exe's: The alias in the App Execution Alias page, and the real one wherever you installed Python. But cmd finds the App execution, alias python.exe, first because that directory is at the top of the Path.
I think the easiest solution is to just check the python.exe and python3.exe to OFF as I suggested before, which deletes the fake EXE file files. Based on this Microsoft Devblog, they stated they created this system partially for new Python users, specifically kids learning Python in school that had trouble installing it.
Creating this alias was to help kids just starting Python to install it and focus on learning to code. I think Windows probably deletes those aliases if you install Python from the Windows App Store. We are noticing that they do not get deleted if you manually install from another source.
(Also, the empty/fake python.exe is not really empty. It says 0 KB in the screenshot, but entering "start ms-windows-store:" in cmd opens the Windows App Store, so it probably just has a line with that and a way to direct it to the Python page.)
Finally, as Chipjust suggested, you can create a new alias for Python using something like DOSKEY as explained in this article for example:
How to set aliases for the command prompt in Windows

The main problem here is that the order in the path calls the windows from top to bottom, and that there is python.exe in %USERPROFILE%\AppData\Local\Microsoft\WindowsApps which is called first if there are no other python.exes in the PATH above that line.
To ensure that the correct python.exe is called, add the Python interpreter installation folder (containing python.exe) to the PATH, above %USERPROFILE%\AppData\Local\Microsoft\WindowsApps
Here is an example:
To get to this location, click "Start" → start typing "Env" → Select "Edit the system environment variables" → "Environment variables" button → Select the entry for "Path" in the upper list → Click "Edit".
Python components should be at the top, as in step 5. If not, move them up by pressing the button in step 6.

If the Python interpreter is already installed, then go to Apps & features from settings, select Python, and then select modify.
Again select modify and select Next:
Then this window will appear:
Select "add Python to environment variable" and click on the install button. Then again go to apps & features, click modify and click Repair.
Now go to CMD and type Python.
Problem solved.

This is a PowerShell script that does the magic.
Remove-Item $env:USERPROFILE\AppData\Local\Microsoft\WindowsApps\python*.exe

I had problems with this as well, where Windows didn't recognize Python or Anaconda in a double click or cmd (command) prompt.
Problem: unable to import libraries in "python" cmd in Windows. Instead the Windows "python" cmd took users somewhere they don't want to go.
Problem Cause: In Windows "Environmental Variables", Windows adds a python.exe and python3.exe (I don't know where these link to) in the "%USERPROFILE%\AppData\Local\Microsoft\WindowsApps" directory.
Solution: I tried deleting the python*.exe files in the WindowsApp directory, but Windows wouldn't allow it, so I opened a command prompt in the "%USERPROFILE%\AppData\Local\Microsoft\WindowsApps" directory and typed:
del python.exe
del python3.exe
Then I created an environment variable linking to the installed Python interpreter link. In my case, it was C:\Anaconda3; C:\Anaconda3\Scripts, and some others for good measure.

Because this is a common issue and this appears to be the canonical question, I want to try to give a complete overview of The Python 3.7 Windows Store Fiasco (TM).
Why is it possible for this to happen?
A convergence of two things: the previous introduction of the Python Launcher for Windows in 2011 (hereafter py), and a Windows 10 update in May 2019 that was apparently intended to make installing Python easier for Windows users.
Oops. Turns out that installation path isn't great; it bypasses the "lengthy" setup wizard... which contains some options that some users find very useful. It caused other issues, too. Not to mention that it just works in slightly non-standard ways, has limitations on file system access because it's a Store app, initially couldn't itself be launched by py....
Okay, but why do those factors result in the problem?
Since the introduction of py, by default, Windows Python installers do not add the new Python install to the PATH. Why? Because the entire point of py is that it uses its own logic to find a Python installation, based on some combination of command-line switches and possibly the source file's own shebang line. Now your source files can be associated with py instead of any particular python.exe, and you can get Linux-like behaviour when double-clicking a file. Meanwhile, by running py at the command line, you have easy access to whatever you need, and you don't have to think about which version of Python was installed most recently. So there's seemingly no good reason to put any of those Python installations on the PATH. It only risks confusing you when, for example, the most recently installed version isn't the most up-to-date one. Right?
In the update, Windows 10 put a "python.exe" into a Windows Apps-related folder, which is a wrapper app to open a Microsoft Store link. The idea is that it's on the PATH, but way near the end; so if you have an installed Python, it gets used, and otherwise the wrapper is invoked and helpfully prompts you to install Python - so that you can actually run that random, totally trusted .py file your friend sent you on Discord.
And it would work perfectly, if your installed Python were on the PATH.
Oops.
(But, you know, py had been introduced around 8 years prior. You'd think someone at Microsoft would have been aware of the potential issue. Maybe instead of a special shortcut link, they could have made an actual script that checks for the presence of C:\Windows\py.exe or something.)
So what are my options?
You can check the option to add new Python versions to the PATH when you install them, and deal with the fact that python at the command line means a specific one of them. If you need to change that, you can manually tweak your PATH variable.
You can just manually tweak the PATH variable after the fact. (or "Modify" a Python installation to fix it.) This is covered in several other answers.
Independently of that, you can disable the wrappers, as shown in the top answer. You should probably do this anyway; seeing python fail at the command line is less aggravating than dealing with a random GUI window popping up and offering to install something for you, especially when you know you have it already.
If you want to keep the PATH empty, consider using virtual environments for your projects. Whenever a virtual environment is active, the PATH is temporarily modified such that python means the Python installation of that environment. It's quite convenient, really.
You might be able to tell your IDEs to use py instead of a specific Python installation, and it might even be helpful to do so. I don't know. I don't use one.

As a person who does Python development in Sublime Text, I know you said the Python interpreter path was correct, but when you install the Python interpreter make sure to tick the option to add Python to PATH.
I had the same issue back in the day till I did this.

You can manually add Python to the Windows path by doing this:
Start the Run box and enter sysdm.cpl
Go to the Advanced tab and click the Environment Variables button
Now you’ll need to locate the relevant Python paths
Here is how a Python application path looks like:
And this is how a Python Scripts path looks like:
Select the Path variable, press edit and add both paths (Python application and Python Scripts)
If it doesn't show, press new instead of edit and fill the New User Variable box
This is how my Variable value looks like:
C:\Users\Ron\AppData\Local\Programs\Python\Python37-32;C:\Users\Ron\AppData\Local\Programs\Python\Python37-32\Scripts
That’s it! You just added Python to the Windows Path.
Source: Data To Fish

So, I had the same problem.
My answer was to add python to PATH not only for User variables, it was there, but also for System variables. And now everything works.
So, I've got the same problem in VENV.
I solved it by typing >> python**.exe**
But to add every time .exe a little bit nervous.
Also try to type python.exe in cmd.

This is an additional note for anyone using pyenv-win: after turning off the application execution aliases, run pyenv rehash. You may also need to close/reopen your CMD or PowerShell window.

I have put together a powershell snippet, which reorders WindowsApps and Python folder so that Python is first. Run this as Admin:
$appsFld="$env:USERPROFILE\AppData\Local\Microsoft\WindowsApps";
$pyPath=(Resolve-Path "$env:USERPROFILE\AppData\Local\Programs\Python\Python*\")
$Env:Path = (($Env:Path.Split(';') | Where-Object { $_ -ne "$appsFld" }) -join ';');
$Env:Path = (($Env:Path.Split(';') | Where-Object { $_ -ne "$pyPath" }) -join ';');
$Env:Path += ";$pyPath";
$Env:Path +=";$appsFld";
[Environment]::SetEnvironmentVariable("PATH", "$Env:Path", "Machine")
Then I can run python just fine:
> python
Python 3.10.7 (tags/v3.10.7:6cc6b13, Sep 5 2022, 14:08:36) [MSC v.1933 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> quit

Adding a bit to the question. Even when I typed pip freeze, it wasn't showing anything.
Here's what I did:
There were multiple instances for the Python application in /AppData/Local/Microsoft/WindowApps.
I deleted those and then it worked.

PyCharm 5.0.1 doesn't resolve builtin modules / methods

My PyCharm 5.0.1 installation does not resolve references to any builtin modules or methods:
As you can see, I have installed python over cygwin.
I already tried:
reinstalling / updating the python installation (from 2.7.9 to 2.7.10)
reinstalling pycharm
adding a interpreter path to the python-skeletons in the pycharm installation directory (this was immediately removed by the ide when saving the settings, implying, that it already is embedded)
removing the interpreter (this removes the warnings, but also the code completion, and import asdflkjasd is valid as well)
adding various paths like /lib/python2.7/site-packages/ to the interpreter packages option
None of these improved the situation.
How can I fix this without installation outside of cygwin alltogether?

This is an update with a much better solution than my previous answer (which I completely missed that OP was asking for a solution that didn't require exactly what I suggested).
Like Carl commented above, updating python-skeletons is actually the way to go, however, if you're using Cygwin, the interpreter paths are a little wonky, and PyCharm won't always automatically add the right paths. For me, PyCharm handled it just fine in version 4.5.4, but not 5.0.4.
You'll find the python builtins in your Pycharm config directory, probably at:
C:\Users\[USERNAME]\.PyCharm50\system\python_stubs\-[RANDOM_STRING_OF_NUMBERS]
Just manually add this path (or paths) to your interpreter and it should resolve your problem. You can do the same for your site-packages folder if that's currently polluting your project structure space.
To get to the right menu:
Click File -> Settings
Navigate to Project -> Project Interpreter
Click the gear on the top right and click "More"
Select your interpreter and click the "Show paths" button on the right
Instead of clicking refresh, as many other posts suggest, click the "Add" button on the right and add your paths
There's a handy screenshot uploaded by r---------k on the updating python-skeletons post that if that helps you.
Try installing the Python package for Windows from
http://www.python.org/download/windows and point PyCharm to that
interpreter instead.
Settings -> Project -> Project Interpreter -> Gear -> Add Local
You may also need to install PyCharm's Python packaging tools (you
should see a link on the bottom of the Project Interpreter page if it
isn't installed already).
While this may not be a perfect solution depending on your workflow
because PyCharm will no longer be using Cygwin's python interpreter,
but this at least got rid of those pesky squiggly red underlines for
me.

I use Windows 10 x64, Python 3.5.1 and PyCharm Community Edition 2016.1.4
I have the same problem and sovled it by runnig PyCharm in admin mode (it is required only once).

#!/usr/bin/env python3.4 within PyCharm project [duplicate]

I have PyCharm 1.5.4 and have used the "Open Directory" option to open the contents of a folder in the IDE.
I have Python version 3.2 selected (it shows up under the "External Libraries" node).
How can I select another version of Python (that I already have installed on my machine) so that PyCharm uses that version instead?

File -> Settings
Preferences->Project Interpreter->Python Interpreters
If it's not listed add it.

I think you are saying that you have python2 and python3 installed and have added a reference to each version under Pycharm > Settings > Project Interpreter
What I think you are asking is how do you have some projects run with Python 2 and some projects running with Python 3.
If so, you can look under Run > Edit Configurations

PyCharm 2019.1+
There is a new feature called Interpreter in status bar (scroll down a little bit). This makes switching between python interpreters and seeing which version you’re using easier.
Enable status bar
In case you cannot see the status bar, you can easily activate it by running the Find Action command (Ctrl+Shift+A or ⌘+ ⇧+A on mac). Then type status bar and choose View: Status Bar to see it.

This can also happen in Intellij Ultimate, which has PyCharm integrated. The issue is as diagnosed above, you have the wrong interpreter selected.
The exact method to fix this for any given project is to go to Project Settings...Project and adjust the Project SDK. You can add a New Project SDK if you don't have Python 3 added by navigating to the python3 binary. This will fix the errors listed above. A shortcut to Project Settings is the blue checkerboard-type icon.
You can also add Python 3 as the default interpreter for Python projects. On OSX this is in File..Other Settings...Default Project Structure. There you can set the Project SDK which will now apply on each new project. It can be different on other platforms, but still similar.

Go to:
Files -> Settings -> Project -> *"Your Project Name"* -> Project Interpreter
There you can see which external libraries you have installed for python2 and which for python3.
Select the required python version according to your requirements.

Quick Answer:
File --> Setting
In left side in project section --> Project interpreter
Select desired Project interpreter
Apply + OK
[NOTE]:
Tested on Pycharm 2018 and 2017.

Trying to get PyCharm to work, keep getting "No Python interpreter selected"

I'm trying to learn Python and decided to use PyCharm. When I try to start a new project I get a dialog that says "No Python interpreter selected". It has a drop down to select a interpreter, but the drop down is empty.

Your problem probably is that you haven't installed python. Meaning that, if you are using Windows, you have not downloaded the installer for Windows, that you can find on the official Python website.
In case you have, chances are that PyCharm cannot find your Python installation because its not in the default location, which is usually C:\Python27 or C:\Python33 (for me at least).
So, if you have installed Python and it still gives this error, then there can be two things that have happened:
You use a virtualenv and that virtualenv has been deleted or the filepath changed. In this case, you will have to find proceed to the next part of this answer.
Your python installation is not in its default place, in which case you will need to find its location, and locate the python.exe file.
Once you have located the necessary binaries, you will need to tell PyCharm were to look:
Open your settings dialogue CTRL + ALT + S
Then you will need to type in interpreter in the search box:
As you can see above, you will need to go to Project Interpreter and then go to Python Interpreter. The location has been selected for you in the above image.
To the side you will see a couple of options as icons, click the big + icon, then click on local, because your interpreter is on this computer.
This will open up a dialogue box. Make sure to select the python.exe file of that directory, do not give pycharm the whole directory. It just wants the interpreter.

Go to File->Settings->Project Settings->Project Interpreter->Python Interpreters
There will be a "+" sign on the right side. Navigate to your python binary, PyCharm will figure out the rest.

This situation occurred to me when I uninstalled a method and tried to reinstall it. My very same interpreter, which worked before, suddenly stopped working. And this error occurred.
I tried restarting my PC, reinstalling Pycharm, invalidating caches, nothing worked.
Then I went here to reinstall the interpreter:
https://www.python.org/downloads/
When you install it, there's an option to fix the python.exe interpreter. Click that. My IDE went back to normal working conditions.

During the install of python make sure you have "Install for all users" selected.
Uninstall python and do a custom install and check "Install for all users".

Even I got the same issue and my mistake was that I didn't download python MSI file. You will get it here: https://www.python.org/downloads/
Once you download the msi, run the setup and that will solve the problem. After that you can go to File->Settings->Project Settings->Project Interpreter->Python Interpreters
and select the python.exe file. (This file will be available at c:\Python34)
Select the python.exe file. That's it.

for mac I can tell you that first you have to check your path
by executing this command
which python or which python3
then you have to configure it in your pycharm.
pycharm-->preferences-->gear button-->add..
click on system interpreter--> then on ...
then you search where your python version is installed
once it is done then you have to configure for your project
click on edit configuration
then choose the python interpreter

If you are using Ubuntu, Python has already been downloaded on your PC.
so, go to -> ctrl + alt + s -> search interpreter -> go to project interpreter than select Python 3.6 in the dropdown menu.
Edit: If there is no Python interpreter in drop-down menu, you should click the gear icon that on the right of the drop-down menu --> add --> select an interpreter.
(on PyCharm 2018.2.4 Community Edition)

I got the same issue when i newly installed pycharm in my windows 10 machine.
download python setup
install this solved my problem.
for more help visit
goodluck
During the install of python make sure you have "Install for all users" selected. Uninstall python and do a custom install and check "Install for all users"

In my case, there are several interpreters, but I have to manually add them.
To the right of where you see "No Interpreters", there is a gear icon. Click the gear icon -> Click "Add...", then you can add the ones you need.

In Linux, it was solved by opening PyCharm from the terminal and leaving it open. After that, I was able to choose the correct interpreter in preferences. In my case, linked to a virtual environment (venv).

You don't have Python Interpreter installed on your machine whereas Pycharm is looking for a Python interpreter, just go to https://www.python.org/downloads/
and download python and then create a new project, you'll be all set!

I had the same problem and stumbled onto this solution.
I ran PyCharm (as administrator, though not sure if necessary).
After PyCharm has completely loaded (green tick mark top right), see bottom right. Click on it.
An interface will open. In my case the path was already there. I just clicked OK and all was fine.
closed PyCharm and ran it again normally. Still all fine.

I has to close PyCharm, delete the .idea folder then open PyCharm again.