No python interpreter configured for the project is a common error message you may encounter in PyCharm. PyCharm is a very useful editor having nice features like debugging, testing, refactoring and code completion. However, it needs an external interpreter (Python.exe) to run Python code.
This message tells you that project configuration should be updated to use a valid Python installation. To open the related configuration, you can click on Configure Python interpreter link as shown below. Or alternatively, you can select File -> Settings from the menu and open Project -> Python Interpreter setting.
Python Interpreter setting shows that <No Interpreter> is selected for the project. To select (or create) a Python.exe interpreter click on Gear icon and select Show All… option.
In the Python Interpreters window that opens, the list is empty. To add a new Python Interpreter click on Plus (+) icon.
In Add Python Interpreter window, you can create a new virtual Python environment. My project is under C:\abcstudyguide\python directory, so I have created a folder venv under this directory to create a new virtual environment for my project.
You must then choose a Base interpreter. Base interpreter is the python.exe file installed on your system. When you create a virtual environment, it will be based on Python version specified here. If you need a specific version of Python (like 3.8, 3.7), you need show path of this Python version in Base interpreter filed.
If you don’t have Python installed on your system yet, you can download it from https://www.python.org/downloads/. Note that I installed Python in C:\Python\Python39 directory on my computer. However, default installation path is C:\Users\{YourUserName}\AppData\Local\Programs\Python.
Virtual Environments in Python
Instead of creating a new virtual environment, you can also use the System Interpreter, but this method is not recommended.
You can work on many different Python projects. Virtual environments are useful for creating an isolated environment for each Python project. Consider you are working on two different projects (ProjectA and ProjectB). Both projects are using the same library (LibraryX) but they require different versions of LibraryX. ProjectA needs version 1.0 of LibraryX, ProjectB needs version 2.0.
To avoid version conflicts between third party libraries, each project should create and use its own virtual environment instead of using System Interpreter (C:\Python\Python39\python.exe).
When you create a new Python virtual environment and select it as Python Interpreter in your project settings, No python interpreter configured for the project message will be gone.
