Develop Reference

Error on visual studio code: Python was not found; run without arguments to install from the Microsoft Store [duplicate]

I was trying to download a GUI, but the terminal kept giving me this error:
Python was not found; run without arguments to install from the Microsoft Store, or disable this shortcut from Settings > Manage App Execution Aliases.
I'm trying to install it using this command:
python -m pip install --upgrade pip setuptools virtualenv

Check your Python version and be sure it is installed on your machine
Check the path environment variable
Go to -> "start" and type "Manage App Execution Aliases". Go to it and turn off "Python"

I was having the same issue and I fixed it by using the below method.
Copy two paths of Python
C:\Users\Maninder\AppData\Local\Programs\Python\Python39
C:\Users\Maninder\AppData\Local\Programs\Python\Python39\Scripts
These are the paths where your Python interpreter is installed. Now add this path into your environmental
variable. Put this path into System variable, not in user variable. I was using user variable, so I was facing the issue.

I have a solution for you. Make sure you check the path mark during installation. Then you need to go to Manage App Execution Aliases.
Simply go to your search bar and search for Manage App Execution Aliases. You will find the attached screen and you need to turn off App Installers as you see on the screen. Also, see the path,,, follow Maninder's answer.
Then you are good to go! :)

I had the same issue. In Windows CMD, only: py --version, works.
I tried adding the path on System variables, and it didn't work. If you are using PyCharm as I do, try to run all commands from the IDE's terminal. It usually is on the side bar where the Run and the Console is. If it is not, go to: menu View → Tool Windows → Terminal. It worked just fine for me.

You need to download Python from https://python.org. When in the installation, be sure to check the option that adds Python to PATH.

I haven't gotten this error before and have been using Python a long time, and then suddenly it showed up. I think that it is a result of a Windows update designed to steer you to their store.
In any case: to remedy the problem, go to Settings → app execution aliases → and turn "off" Python. (What they tell you to do, in other words). This should resolve the problem.

If you have installed Python successfully with add python path, ticked on, and have added
C:\Users\<user>\AppData\Local\Programs\Python\Python39
C:\Users\<user>\AppData\Local\Programs\Python\Python39\Scripts
to the path into System variables and have turned off the "aliases" and they all didn't work, you can simply use python instead of python3 in your cmd command.

Check the Aliases for App Execution in Windows. Search for Alias App in your Windows toolbar to find the UI for this. Try turning off anything Python related.

Try adding the following to your "Path" environment variable:
C:\Users\Default\AppData\Local\Programs\Python\Python37
C:\Users\Default\AppData\Local\Programs\Python\Python37\Scripts
Replace Python37 with your own version.

I solved this problem for Visual Studio Code with just writing "python" in the console:
python
After that, Microsoft Store opens automatically with the Python app:
And I just click Get.
And it all work!

All the previous answers are correct, but in my case, I was getting this, because I was not passing the version...
The fix is passing the version:
py.exe -3 your_program

If you're on Windows, you may want to use the Python installer, in Windows Marketplace.

I faced the same error while using Anaconda and trying to link the Python executable path in the command prompt.
It got rectified by going to Settings → App execution aliases → and turning "off" Python. Then again I had to set the path for Python in Anaconda and was successful in executing "python --version" command.

The same thing happened to me even after trying all the above-mentioned steps.
I just restart my system and it was working fine. Do it and if still doesn't fix the issue then make sure you have checked "add python ( any version ) to PATH" before installing Python.

If none of the previous answers are working, you can check if you have the Python executable in your program files.
Go to C:\Program Files and check if you have the Python application. If not, go to the python download website here and download the .exe file.
While installing you must select "Custom install" and select the location as C:/Program Files.
Install it and it should work now from anywhere. This worked for me!

To sincerely resolve this issue, do the following:
Uninstall the Python instance and reinstall it. Note: Make sure you check
"Add variable PATH".
On the command line, type:
python -m pip install --upgrade pip setuptools virtualenv

I got this issue when I used Visual Studio Code as the IDE, and Anaconda as my Python compiler. And you don't need to close the "app alias" in settings, but copy your python.exe to python3.exe in your Anaconda folder.

That happened to me. So, to fix it, you have to follow the following steps:
Uninstall the Python version you already installed.
Go ahead and open the installation file to reinstall it again.
Before hitting Install Now, make sure to tick the box in front of Add Python to path.
Go ahead and complete the installation procedure as usual.
Steps for installing Python

The problem is more subtle than it seems.
For example, if you are using Visual Studio Code on the bottom left, you should see Python X.X.X xx-bit (the X is the version).
If you click in there you will see where the IDE is getting the python.exe from.
Locate that folder into your file explorer and then just follow the answer that is saying to change the environments variables.
So copy the path where python.exe is and add it to the Path variable and do the same where the Script folder is (it is in the same directory where the python.exe is).
Then of course make sure your IDE is using the right Python.

None of the answers here worked for me. I did this and the error went away.
For Windows 11 which I was using, I reran the python-3.10.5-amd64.exe file from my downloads directory and then chose to modify the installation.
Then I followed these easy steps.
Make sure the PIP component is checked before proceeding to install.
Then check 'Add Python to environment variables' if it's not checked already.
Proceed to Install.
At this point, your error will be solved

If you already have the Python executable on your machine and you are getting this error in Windows 10, search for the Python executable and copy its path then copy the path in system variables. It worked for me.

to check in windows
py --version
or restart your pc first then put htis command again

I keep getting this error on every IDE: ModuleNotFoundError: No module named 'pygame' [duplicate]

I'm having trouble with using 'requests' module on my Mac. I use python34 and I installed 'requests' module via pip. I can verify this via running installation again and it'll show me that module is already installed.
15:49:29|mymac [~]:pip install requests
Requirement already satisfied (use --upgrade to upgrade): requests in /opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages
Although I can import 'requests' module via interactive Python interpreter, trying to execute 'import requests' in PyCharm yields error 'No module named requests'. I checked my PyCharm Python interpreter settings and (I believe) it's set to same python34 as used in my environment. However, I can't see 'requests' module listed in PyCharm either.
It's obvious that I'm missing something here. Can you guys advise where should I look or what should I fix in order to get this module working? I was living under impression that when I install module via pip in my environment, PyCharm will detect these changes. However, it seems something is broken on my side ...

In my case, using a pre-existing virtualenv did not work in the editor - all modules were marked as unresolved reference (running naturally works, as this is outside of the editor's config, just running an external process (not so easy for debugging)).
Turns out PyCharm did not add the site-packages directory... the fix is to manually add it.
On Pycharm professional 2022.3
Open File -> Settings -> Python Interpreter, open the drop-down and pick "Show All..." (to edit the config) (1), right click your interpreter (2), click "Show Interpreter Paths" (3).
In that screen, manually add the "site-packages" directory of the virtual environment [looks like .../venv/lib/python3.8/site-packages (4) (I've added the "Lib" also, for a good measure); once done and saved, they will turn up in the interpreter paths.
The other thing that won't hurt to do is select "Associate this virtual environment with the current project", in the interpreter's edit box.

If you are using PyCharms CE (Community Edition), then click on:
File->Default Settings->Project Interpreter
See the + sign at the bottom, click on it. It will open another dialog with a host of modules available. Select your package (e.g. requests) and PyCharm will do the rest.

This issue arises when the package you're using was installed outside of the environment (Anaconda or virtualenv, for example). In order to have PyCharm recognize packages installed outside of your particular environment, execute the following steps:
Go to
Preferences -> Project -> Project Interpreter -> 3 dots -> Show All ->
Select relevant interpreter -> click on tree icon Show paths for the selected interpreter
Now check what paths are available and add the path that points to the package installation directory outside of your environment to the interpreter paths.
To find a package location use:
$ pip show gym
Name: gym
Version: 0.13.0
Summary: The OpenAI Gym: A toolkit for developing and comparing your reinforcement learning agents.
Home-page: https://github.com/openai/gym
Author: OpenAI
Author-email: gym#openai.com
License: UNKNOWN
Location: /usr/local/lib/python3.7/site-packages
...
Add the path specified under Location to the interpreter paths, here
/usr/local/lib/python3.7/site-packages
Then, let indexing finish and perhaps additionally reopen your project.

Open python console of your pyCharm. Click on Rerun.
It will say something like following on the very first line
/System/Library/Frameworks/Python.framework/Versions/2.7/bin/python2.7 /Applications/PyCharm.app/Contents/helpers/pydev/pydevconsole.py 52631 52632
in this scenario pyCharm is using following interpretor
/System/Library/Frameworks/Python.framework/Versions/2.7/bin/python2.7
Now fire up console and run following command
sudo /System/Library/Frameworks/Python.framework/Versions/2.7/bin/python2.7 -m pip install <name of the package>
This should install your package :)

Pycharm is unable to recognize installed local modules, since python interpreter selected is wrong. It should be the one, where your pip packages are installed i.e. virtual environment.
I had installed packages via pip in Windows. In Pycharm, they were neither detected nor any other Python interpreter was being shown (only python 3.6 is installed on my system).
I restarted the IDE. Now I was able to see python interpreter created in my virtual environment. Select that python interpreter and all your packages will be shown and detected. Enjoy!

Using dual python 2.7 and 3.4 with 2.7 as default, I've always used pip3 to install modules for the 3.4 interpreter, and pip to install modules for the 2.7 interpreter.
Try this:
pip3 install requests

This is because you have not selected two options while creating your project:-
** inherit global site packages
** make available to all projects
Now you need to create a new project and don't forget to tick these two options while selecting project interpreter.

The solution is easy (PyCharm 2021.2.3 Community Edition).
I'm on Windows but the user interface should be the same.
In the project tree, open External libraries > Python interpreter > venv > pyvenv.cfg.
Then change:
include-system-site-packages = false
to:
include-system-site-packages = true

Before going further, I want to point out how to configure a Python interpreter in PyCharm: [SO]: How to install Python using the "embeddable zip file" (#CristiFati's answer). Although the question is for Win, and has some particularities, configuring PyCharm is generic enough and should apply to any situation (with minor changes).
There are multiple possible reasons for this behavior.
1. Python instance mismatch
Happens when there are multiple Python instances (installed, VEnvs, Conda, custom built, ...) on a machine. Users think they're using one particular instance (with a set of properties (installed packages)), but in fact they are using another (with different properties), hence the confusion. It's harder to figure out things when the 2 instances have the same version (and somehow similar locations)
Happens mostly due to environmental configuration (whichever path comes 1st in ${PATH}, aliases (on Nix), ...)
It's not PyCharm specific (meaning that it's more generic, also happens outside it), but a typical PyCharm related example is different console interpreter and project interpreter, leading to confusion
The fix is to specify full paths (and pay attention to them) when using tools like Python, PIP, .... Check [SO]: How to install a package for a specific Python version on Windows 10? (#CristiFati's answer) for more details
This is precisely the reason why this question exists. There are 2 Python versions involved:
Project interpreter: /Library/Frameworks/Python.framework/Versions/3.4
Interpreter having the Requests module: /opt/local/Library/Frameworks/Python.framework/Versions/3.4
well, assuming the 2 paths are not somehow related (SymLinked), but in latest OSX versions that I had the chance to check (Catalina, Big Sur, Monterey) this doesn't happen (by default)
When dealing with this kind of error, it always helps (most likely) displaying the following information (in a script or interpreter console):
import os
import sys
print(sys.executable)
print(sys.version)
print(os.getcwd())
print(getattr(os, "uname", lambda: None)())
print(sys.path)
2. Python's module search mechanism misunderstanding
According to [Python.Docs]: Modules - The Module Search Path:
When a module named spam is imported, the interpreter first searches for a built-in module with that name. These module names are listed in sys.builtin_module_names. If not found, it then searches for a file named spam.py in a list of directories given by the variable sys.path. sys.path is initialized from these locations:
The directory containing the input script (or the current directory when no file is specified).
PYTHONPATH (a list of directory names, with the same syntax as the shell variable PATH).
The installation-dependent default (by convention including a site-packages directory, handled by the site module).
A module might be located in the current dir, or its path might be added to ${PYTHONPATH}. That could trick users into making them believe that the module is actually installed in the current Python instance ('s site-packages). But, when running the current Python instance from a different dir (or with different ${PYTHONPATH}) the module would be missing, yielding lots of headaches
For a fix, check [SO]: How PyCharm imports differently than system command prompt (Windows) (#CristiFati's answer)
3. A PyCharm bug
Not very likely, but it could happen. An example (not related to this question): [SO]: PyCharm 2019.2 not showing Traceback on Exception (#CristiFati's answer)
To fix, follow one of the options from the above URL
4. A glitch
Not likely, but mentioning anyway. Due to some cause (e.g.: HW / SW failure), the system ended up in an inconsistent state, yielding all kinds of strange behaviors
Possible fixes:
Restart PyCharm
Restart the machine
Recreate the project (remove the .idea dir from the project)
Reset PyCharm settings: from menu select File -> Manage IDE Settings -> Restore Default Settings.... Check [JetBrains]: Configuring PyCharm settings or [JetBrains.IntelliJ-Support]: Changing IDE default directories used for config, plugins, and caches storage for more details
Reinstall PyCharm
Needless to say that the last 2 options should only be attempted as a last resort, and only by experts, as they might mess up other projects and not even fix the problem
Not directly related to the question, but posting:
[SO]: Run / Debug a Django application's UnitTests from the mouse right click context menu in PyCharm Community Edition? (a PyCharm related investigation from a while ago)
[SO]: ImportError: No module named win32com.client (#CristiFati's answer)

If you go to pycharm project interpreter -> clicked on one of the installed packages then hover -> you will see where pycharm is installing the packages. This is where you are supposed to have your package installed.
Now if you did sudo -H pip3 install <package>
pip3 installs it to different directory which is /usr/local/lib/site-packages
since it is different directory from what pycharm knows hence your package is not showing in pycharm.
Solution: just install the package using pycharm by going to File->Settings->Project->Project Interpreter -> click on (+) and search the package you want to install and just click ok.
-> you will be prompted package successfully installed and you will see it pycharm.

If any one faces the same problem that he/she installs the python packages but the PyCharm IDE doesn't shows these packages then following the following steps:
Go to the project in the left side of the PyCharm IDE then
Click on the venv library then
Open the pyvenv.cfg file in any editor then
Change this piece of code (include-system-site-packages = flase) from false to true
Then save it and close it and also close then pycharm then
Open PyCharm again and your problem is solved.
Thanks

This did my head in as well, and turns out, the only thing I needed to do is RESTART Pycharm. Sometimes after you've installed the pip, you can't load it into your project, even if the pip shows as installed in your Settings. Bummer.

For Anaconda:
Start Anaconda Navigator -> Enviroments -> "Your_Enviroment" -> Update Index -> Restart IDE.
Solved it for me.

After pip installing everything I needed. I went to the interpreter and re-pointed it back to where it was at already.
My case: python3.6 in /anaconda3/bin/python using virtualenv...
Additionally, before I hit the plus "+" sign to install a new package. I had to deselect the conda icon to the right of it. Seems like it would be the opposite, but only then did it recognize the packages I had/needed via query.

In my case the packages were installed via setup.py + easy_install, and the they ends up in *.egg directories in site_package dir, which can be recognized by python but not pycharm.
I removed them all then reinstalled with pip install and it works after that, luckily the project I was working on came up with a requirements.txt file, so the command for it was:
pip install -r ./requirement.txt

I just ran into this issue in a brand new install/project, but I'm using the Python plugin for IntelliJ IDEA. It's essentially the same as PyCharm but the project settings are a little different. For me, the project was pointing to the right Python virtual environment but not even built-in modules were being recognized.
It turns out the SDK classpath was empty. I added paths for venv/lib/python3.8 and venv/lib/python3.8/site-packages and the issue was resolved. File->Project Structure and under Platform Settings, click SDKs, select your Python SDK, and make sure the class paths are there.

pip install --user discord
above command solves my problem, just use the "--user" flag

I fixed my particular issue by installing directly to the interpreter. Go to settings and hit the "+" below the in-use interpreter then search for the package and install. I believe I'm having the issue in the first place because I didn't set up with my interpreter correctly with my venv (not exactly sure, but this fixed it).
I was having issues with djangorestframework-simplejwt because it was the first package I hadn't installed to this interpreter from previous projects before starting the current one, but should work for any other package that isn't showing as imported. To reiterate though I think this is a workaround that doesn't solve the setup issue causing this.

If you are having issues with the underlying (i.e. pycharm's languge server) mark everything as root and create a new project. See details: https://stackoverflow.com/a/73418320/1601580 this seems to happy to me only when I install packages as in editable mode with pip (i.e. pip install -e . or conda develop). Details: https://stackoverflow.com/a/73418320/1601580

--WINDOWS--
if using Pycharm GUI package installer works fine for installing packages for your virtual environment but you cannot do the same in the terminal,
this is because you did not setup virtual env in your terminal, instead, your terminal uses Power Shell which doesn't use your virtual env
there should be (venv) before you're command line as shown instead of (PS)
if you have (PS), this means your terminal is using Power Shell instead of cmd
to fix this, click on the down arrow and select the command prompt
select command prompt
now you will get (venv) and just type pip install #package name# and the package will be added to your virtual environment

On windows I had to cd into the venv folder and then cd into the scripts folder, then pip install module started to work
cd venv
cd scripts
pip install module

instead of running pip install in the terminal -> local use terminal -> command prompt
see below image
pycharm_command_prompt_image

In your pycharm terminal run pip/pip3 install package_name

Avast blocks pip and Pyinstaller

I'm making a Simple GUI Tkinter Program. I was going to compile my Program (with Pyinstaller) but Avast is blocking PIP. So I ignored it. When Compile was Finished.
I run the compiled .exe program and the program are saying:
failed to execute the script, Avast is blocking.
How to fix this error and What am the issue?
edit:now Avast is not blocking .exe(but blocking PIP)

I use avast as well. Avast sandboxes pipenv when installing a new package. Depending on what/if virtualenv your using.
You can whitelist/exclude python's install directory. For windows the default location is %localappdata%\Programs\Python. This is also where pip is installed globally as well as pyinstaller and other packages that are installed globally.
Be warned this will make it so avast no longer scans anything related to python in those directories. So if you're worried about getting a virus from a python package then you can whitelist/exclude the pip exe itself which is located specifically...
32-bit Python 3.8
%localappdata%\Programs\Python\Python38-32\Scripts\pip.exe
64-bit Python 3.8
%localappdata%\Programs\Python\Python38\Scripts\pip.exe
If you use a virtualenv whitelist/exclude those directories since those virtualenvs use a local copy of pip instead of the global one. That should fix avast messing with pip/virtualenv/pipenv

Just to mention it according to the steps found in https://support.avast.com/en-gb/article/Antivirus-scan-exclusions/ you need to do the following to get pip whitelisted on Avast:
STEPS
Open Avast Antivirus and go to ☰ Menu ▸ Settings.
Select General ▸ Exceptions, then click Add exception.
Add an exception in one of the following ways:
Type the specific file/folder path or URL into the text box, then click Add exception.
Click Browse, tick the box next to a file or folder, For example in x64 system: HOME_DIRECTORY\AppData\Local\Programs\Python\Python39\Scripts\pip.exe (depending on your version of python), then click OK.
Click Add Exeption
Your specified files, folder, or website is added to the exceptions list.
NOTE: You can select or add multiple files so its good to select pip.exe and pip3.exe and pip39.exe, depending on what python version you are using and what pip files you have in the folder

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.

PyCharm doesn't recognize installed module

I'm having trouble with using 'requests' module on my Mac. I use python34 and I installed 'requests' module via pip. I can verify this via running installation again and it'll show me that module is already installed.
15:49:29|mymac [~]:pip install requests
Requirement already satisfied (use --upgrade to upgrade): requests in /opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages
Although I can import 'requests' module via interactive Python interpreter, trying to execute 'import requests' in PyCharm yields error 'No module named requests'. I checked my PyCharm Python interpreter settings and (I believe) it's set to same python34 as used in my environment. However, I can't see 'requests' module listed in PyCharm either.
It's obvious that I'm missing something here. Can you guys advise where should I look or what should I fix in order to get this module working? I was living under impression that when I install module via pip in my environment, PyCharm will detect these changes. However, it seems something is broken on my side ...

In my case, using a pre-existing virtualenv did not work in the editor - all modules were marked as unresolved reference (running naturally works, as this is outside of the editor's config, just running an external process (not so easy for debugging)).
Turns out PyCharm did not add the site-packages directory... the fix is to manually add it.
On Pycharm professional 2022.3
Open File -> Settings -> Python Interpreter, open the drop-down and pick "Show All..." (to edit the config) (1), right click your interpreter (2), click "Show Interpreter Paths" (3).
In that screen, manually add the "site-packages" directory of the virtual environment [looks like .../venv/lib/python3.8/site-packages (4) (I've added the "Lib" also, for a good measure); once done and saved, they will turn up in the interpreter paths.
The other thing that won't hurt to do is select "Associate this virtual environment with the current project", in the interpreter's edit box.

If you are using PyCharms CE (Community Edition), then click on:
File->Default Settings->Project Interpreter
See the + sign at the bottom, click on it. It will open another dialog with a host of modules available. Select your package (e.g. requests) and PyCharm will do the rest.

This issue arises when the package you're using was installed outside of the environment (Anaconda or virtualenv, for example). In order to have PyCharm recognize packages installed outside of your particular environment, execute the following steps:
Go to
Preferences -> Project -> Project Interpreter -> 3 dots -> Show All ->
Select relevant interpreter -> click on tree icon Show paths for the selected interpreter
Now check what paths are available and add the path that points to the package installation directory outside of your environment to the interpreter paths.
To find a package location use:
$ pip show gym
Name: gym
Version: 0.13.0
Summary: The OpenAI Gym: A toolkit for developing and comparing your reinforcement learning agents.
Home-page: https://github.com/openai/gym
Author: OpenAI
Author-email: gym#openai.com
License: UNKNOWN
Location: /usr/local/lib/python3.7/site-packages
...
Add the path specified under Location to the interpreter paths, here
/usr/local/lib/python3.7/site-packages
Then, let indexing finish and perhaps additionally reopen your project.

Open python console of your pyCharm. Click on Rerun.
It will say something like following on the very first line
/System/Library/Frameworks/Python.framework/Versions/2.7/bin/python2.7 /Applications/PyCharm.app/Contents/helpers/pydev/pydevconsole.py 52631 52632
in this scenario pyCharm is using following interpretor
/System/Library/Frameworks/Python.framework/Versions/2.7/bin/python2.7
Now fire up console and run following command
sudo /System/Library/Frameworks/Python.framework/Versions/2.7/bin/python2.7 -m pip install <name of the package>
This should install your package :)

Pycharm is unable to recognize installed local modules, since python interpreter selected is wrong. It should be the one, where your pip packages are installed i.e. virtual environment.
I had installed packages via pip in Windows. In Pycharm, they were neither detected nor any other Python interpreter was being shown (only python 3.6 is installed on my system).
I restarted the IDE. Now I was able to see python interpreter created in my virtual environment. Select that python interpreter and all your packages will be shown and detected. Enjoy!

Using dual python 2.7 and 3.4 with 2.7 as default, I've always used pip3 to install modules for the 3.4 interpreter, and pip to install modules for the 2.7 interpreter.
Try this:
pip3 install requests

This is because you have not selected two options while creating your project:-
** inherit global site packages
** make available to all projects
Now you need to create a new project and don't forget to tick these two options while selecting project interpreter.

The solution is easy (PyCharm 2021.2.3 Community Edition).
I'm on Windows but the user interface should be the same.
In the project tree, open External libraries > Python interpreter > venv > pyvenv.cfg.
Then change:
include-system-site-packages = false
to:
include-system-site-packages = true

Before going further, I want to point out how to configure a Python interpreter in PyCharm: [SO]: How to install Python using the "embeddable zip file" (#CristiFati's answer). Although the question is for Win, and has some particularities, configuring PyCharm is generic enough and should apply to any situation (with minor changes).
There are multiple possible reasons for this behavior.
1. Python instance mismatch
Happens when there are multiple Python instances (installed, VEnvs, Conda, custom built, ...) on a machine. Users think they're using one particular instance (with a set of properties (installed packages)), but in fact they are using another (with different properties), hence the confusion. It's harder to figure out things when the 2 instances have the same version (and somehow similar locations)
Happens mostly due to environmental configuration (whichever path comes 1st in ${PATH}, aliases (on Nix), ...)
It's not PyCharm specific (meaning that it's more generic, also happens outside it), but a typical PyCharm related example is different console interpreter and project interpreter, leading to confusion
The fix is to specify full paths (and pay attention to them) when using tools like Python, PIP, .... Check [SO]: How to install a package for a specific Python version on Windows 10? (#CristiFati's answer) for more details
This is precisely the reason why this question exists. There are 2 Python versions involved:
Project interpreter: /Library/Frameworks/Python.framework/Versions/3.4
Interpreter having the Requests module: /opt/local/Library/Frameworks/Python.framework/Versions/3.4
well, assuming the 2 paths are not somehow related (SymLinked), but in latest OSX versions that I had the chance to check (Catalina, Big Sur, Monterey) this doesn't happen (by default)
When dealing with this kind of error, it always helps (most likely) displaying the following information (in a script or interpreter console):
import os
import sys
print(sys.executable)
print(sys.version)
print(os.getcwd())
print(getattr(os, "uname", lambda: None)())
print(sys.path)
2. Python's module search mechanism misunderstanding
According to [Python.Docs]: Modules - The Module Search Path:
When a module named spam is imported, the interpreter first searches for a built-in module with that name. These module names are listed in sys.builtin_module_names. If not found, it then searches for a file named spam.py in a list of directories given by the variable sys.path. sys.path is initialized from these locations:
The directory containing the input script (or the current directory when no file is specified).
PYTHONPATH (a list of directory names, with the same syntax as the shell variable PATH).
The installation-dependent default (by convention including a site-packages directory, handled by the site module).
A module might be located in the current dir, or its path might be added to ${PYTHONPATH}. That could trick users into making them believe that the module is actually installed in the current Python instance ('s site-packages). But, when running the current Python instance from a different dir (or with different ${PYTHONPATH}) the module would be missing, yielding lots of headaches
For a fix, check [SO]: How PyCharm imports differently than system command prompt (Windows) (#CristiFati's answer)
3. A PyCharm bug
Not very likely, but it could happen. An example (not related to this question): [SO]: PyCharm 2019.2 not showing Traceback on Exception (#CristiFati's answer)
To fix, follow one of the options from the above URL
4. A glitch
Not likely, but mentioning anyway. Due to some cause (e.g.: HW / SW failure), the system ended up in an inconsistent state, yielding all kinds of strange behaviors
Possible fixes:
Restart PyCharm
Restart the machine
Recreate the project (remove the .idea dir from the project)
Reset PyCharm settings: from menu select File -> Manage IDE Settings -> Restore Default Settings.... Check [JetBrains]: Configuring PyCharm settings or [JetBrains.IntelliJ-Support]: Changing IDE default directories used for config, plugins, and caches storage for more details
Reinstall PyCharm
Needless to say that the last 2 options should only be attempted as a last resort, and only by experts, as they might mess up other projects and not even fix the problem
Not directly related to the question, but posting:
[SO]: Run / Debug a Django application's UnitTests from the mouse right click context menu in PyCharm Community Edition? (a PyCharm related investigation from a while ago)
[SO]: ImportError: No module named win32com.client (#CristiFati's answer)

If you go to pycharm project interpreter -> clicked on one of the installed packages then hover -> you will see where pycharm is installing the packages. This is where you are supposed to have your package installed.
Now if you did sudo -H pip3 install <package>
pip3 installs it to different directory which is /usr/local/lib/site-packages
since it is different directory from what pycharm knows hence your package is not showing in pycharm.
Solution: just install the package using pycharm by going to File->Settings->Project->Project Interpreter -> click on (+) and search the package you want to install and just click ok.
-> you will be prompted package successfully installed and you will see it pycharm.

If any one faces the same problem that he/she installs the python packages but the PyCharm IDE doesn't shows these packages then following the following steps:
Go to the project in the left side of the PyCharm IDE then
Click on the venv library then
Open the pyvenv.cfg file in any editor then
Change this piece of code (include-system-site-packages = flase) from false to true
Then save it and close it and also close then pycharm then
Open PyCharm again and your problem is solved.
Thanks

This did my head in as well, and turns out, the only thing I needed to do is RESTART Pycharm. Sometimes after you've installed the pip, you can't load it into your project, even if the pip shows as installed in your Settings. Bummer.

For Anaconda:
Start Anaconda Navigator -> Enviroments -> "Your_Enviroment" -> Update Index -> Restart IDE.
Solved it for me.

After pip installing everything I needed. I went to the interpreter and re-pointed it back to where it was at already.
My case: python3.6 in /anaconda3/bin/python using virtualenv...
Additionally, before I hit the plus "+" sign to install a new package. I had to deselect the conda icon to the right of it. Seems like it would be the opposite, but only then did it recognize the packages I had/needed via query.

In my case the packages were installed via setup.py + easy_install, and the they ends up in *.egg directories in site_package dir, which can be recognized by python but not pycharm.
I removed them all then reinstalled with pip install and it works after that, luckily the project I was working on came up with a requirements.txt file, so the command for it was:
pip install -r ./requirement.txt

I just ran into this issue in a brand new install/project, but I'm using the Python plugin for IntelliJ IDEA. It's essentially the same as PyCharm but the project settings are a little different. For me, the project was pointing to the right Python virtual environment but not even built-in modules were being recognized.
It turns out the SDK classpath was empty. I added paths for venv/lib/python3.8 and venv/lib/python3.8/site-packages and the issue was resolved. File->Project Structure and under Platform Settings, click SDKs, select your Python SDK, and make sure the class paths are there.

pip install --user discord
above command solves my problem, just use the "--user" flag

I fixed my particular issue by installing directly to the interpreter. Go to settings and hit the "+" below the in-use interpreter then search for the package and install. I believe I'm having the issue in the first place because I didn't set up with my interpreter correctly with my venv (not exactly sure, but this fixed it).
I was having issues with djangorestframework-simplejwt because it was the first package I hadn't installed to this interpreter from previous projects before starting the current one, but should work for any other package that isn't showing as imported. To reiterate though I think this is a workaround that doesn't solve the setup issue causing this.

If you are having issues with the underlying (i.e. pycharm's languge server) mark everything as root and create a new project. See details: https://stackoverflow.com/a/73418320/1601580 this seems to happy to me only when I install packages as in editable mode with pip (i.e. pip install -e . or conda develop). Details: https://stackoverflow.com/a/73418320/1601580

--WINDOWS--
if using Pycharm GUI package installer works fine for installing packages for your virtual environment but you cannot do the same in the terminal,
this is because you did not setup virtual env in your terminal, instead, your terminal uses Power Shell which doesn't use your virtual env
there should be (venv) before you're command line as shown instead of (PS)
if you have (PS), this means your terminal is using Power Shell instead of cmd
to fix this, click on the down arrow and select the command prompt
select command prompt
now you will get (venv) and just type pip install #package name# and the package will be added to your virtual environment

On windows I had to cd into the venv folder and then cd into the scripts folder, then pip install module started to work
cd venv
cd scripts
pip install module

instead of running pip install in the terminal -> local use terminal -> command prompt
see below image
pycharm_command_prompt_image

In your pycharm terminal run pip/pip3 install package_name