Understanding ModuleNotFoundError: Resolving Import Issues in Python Outside of PyCharm

Learn why Python handles module imports differently inside and outside PyCharm, and discover how to fix `ModuleNotFoundError` when running your project from the command line.
---

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: ModuleNotFoundError: Python files seem to behave differentely inside and outside of Pycharm

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Understanding ModuleNotFoundError: Resolving Import Issues in Python Outside of PyCharm

When developing a Python project, encountering errors can be frustrating. One common issue is the ModuleNotFoundError, which can manifest differently depending on the environment in which you run your code. Specifically, you might find that Python files behave differently inside the PyCharm IDE compared to when you run them from the command line. In this post, we’ll explore why this happens and provide a clear solution.

The Problem: ModuleNotFoundError Explained

You may have experienced the following scenario: after successfully running your Python project in PyCharm, you decide to execute the same code using the command line and receive an error message like this:

[[See Video to Reveal this Text or Code Snippet]]

Why Does This Happen?

In your project, you might have a structure that looks like this:

[[See Video to Reveal this Text or Code Snippet]]

Here’s a breakdown of what is going on:

In the Command Line: However, when you execute the command:

[[See Video to Reveal this Text or Code Snippet]]

only the src directory is considered in PYTHONPATH, not the parent directory that contains src. As a result, the interpreter is unable to locate the src module, leading to the ModuleNotFoundError.

The Solution: Emulating PyCharm's Behavior

To resolve this issue and run your code successfully from the terminal, you can follow this simple solution:

Modify the PYTHONPATH When Running from the Command Line

You need to explicitly tell Python to include the project root in its search path. You can achieve this by modifying the PYTHONPATH when you run your Python script. Use the following command in your terminal:

[[See Video to Reveal this Text or Code Snippet]]

Explanation of the Command

PYTHONPATH=.: This sets the PYTHONPATH to the current directory (the root of the project).

By incorporating this change, your Python environment will have access to the necessary modules, allowing for successful imports without any ModuleNotFoundError.

Conclusion

In summary, understanding the differences in module path resolution between PyCharm and the command line is crucial for smooth Python development. By configuring PYTHONPATH accordingly, you can ensure that your project runs seamlessly regardless of the environment.

Next time you encounter import issues outside of PyCharm, remember this workaround to keep your code running smoothly. Happy coding!