How do I find the location of Python module sources?

python

venv

pip

debugging-info

byAnton Shumikhin·Dec 9, 2024

Looking to find where a Python module's source file is hiding? Use the magic powers of the inspect module:

import inspect

# Gotta replace 'your_module' with the alias of your "seek and find" adventure
try:
    module_path = inspect.getfile(your_module)
except TypeError:
    # Uh-oh, we've got a native or compiled module here!
    module_path = 'Native or compiled module without a Python source file'
finally:
    print(module_path)

This bad boy will find and print the file path for your_module if it's a regular Python script. If it's a compiled module, though, it'll let you know.

Distinguishing between module types

Python modules are like snowflakes. No two are alike. Well, sort of. Some modules are written in Python, others are written in low-level languages like C.

For the Python heads

Your module's .__file__ attribute will direct you to the Python source file, like reaching the end of the rainbow.

import some_module_that_exists
print(some_module_that_exists.__file__)

For those living on the edge with compiled modules

Compiled modules can be a sneaky bunch. When you're dealing with them, .__file__ will just lead you to the compiled file. To find their logic, you might have to decipher hieroglyphics in the form of C code.

A couple of sneaky techniques to locate module sources

Fun with the command line

Running python -v will be like your personal detective, keeping track of all those imports and giving you some good ol' debugging info to boot. Who needs Sherlock Holmes?

The power of sys and pip

The pip show <module> command will spill the beans on where a Python module is installed. Double down on your info-gathering by looking at sys.path. It's like a treasure map showing all the directories Python scans when it's seeking out modules:

import sys
print(sys.path)  # Spill the beans, Python!

Diving into the world of C

C extensions can be cunning, and might hide away in the .c files in the Python source tarball or on the Cpython Github repository. It's like finding Waldo, but for code.

What's the deal with virtual environments?

Virtual environments can mix things up a bit. Use pip show <module> or look in your venv's site-packages if you're having a hard time locating the module sources.

Troubleshooting tips

Sometimes, using all your tricks can still leave you scratching your head:

There's no silver bullet to pinpoint the exact file defining a certain module. Overrides and extensions keep everything spicy.
Cross-platform differences can make the location of module sources feel like a game of hide and seek.
Running Python with -v can churn out additional debugging info that can help when you're stuck.

Getting your hands dirty with native modules

Some modules like datetime are native Python modules:

import datetime
print(datetime.__file__)  # Unlocking the "Lock" here!

For native modules, .__file__ might return a .so file, which is just the compiled version. You'll need to head over to their .c counterparts for their source code.