How to Find the Location of Python Module Sources

How do I find the location of Python module sources?

For a pure python module you can find the source by looking at themodule.__file__.
The datetime module, however, is written in C, and therefore datetime.__file__ points to a .so file (there is no datetime.__file__ on Windows), and therefore, you can't see the source.

If you download a python source tarball and extract it, the modules' code can be found in the Modules subdirectory.

For example, if you want to find the datetime code for python 2.6, you can look at

Python-2.6/Modules/datetimemodule.c

You can also find the latest version of this file on github on the web at
https://github.com/python/cpython/blob/main/Modules/_datetimemodule.c

How to retrieve a module's path?

import a_module
print(a_module.__file__)

Will actually give you the path to the .pyc file that was loaded, at least on Mac OS X. So I guess you can do:

import os
path = os.path.abspath(a_module.__file__)

You can also try:

path = os.path.dirname(a_module.__file__)

To get the module's directory.

Where are the python modules stored?

Is there a way to obtain a list of
Python modules available (i.e.
installed) on a machine?

This works for me:

help('modules')

Where is the module code actually
stored on my machine?

Usually in /lib/site-packages in your Python folder. (At least, on Windows.)

You can use sys.path to find out what directories are searched for modules.

How do I find the location of my Python site-packages directory?

There are two types of site-packages directories, global and per user.

Global site-packages ("dist-packages") directories are listed in sys.path when you run:
```
 python -m site
```
For a more concise list run getsitepackages from the site module in Python code:
```
 python -c 'import site; print(site.getsitepackages())'
```
Caution: In virtual environments getsitepackages is not available with older versions of virtualenv, sys.path from above will list the virtualenv's site-packages directory correctly, though. In Python 3, you may use the sysconfig module instead:
```
 python3 -c 'import sysconfig; print(sysconfig.get_paths()["purelib"])'
```
The per user site-packages directory (PEP 370) is where Python installs your local packages:
```
 python -m site --user-site
```
If this points to a non-existing directory check the exit status of Python and see python -m site --help for explanations.
Hint: Running pip list --user or pip freeze --user gives you a list of all installed per user site-packages.

Practical Tips

<package>.__path__ lets you identify the location(s) of a specific package: (details)

  $ python -c "import setuptools as _; print(_.__path__)"
  ['/usr/lib/python2.7/dist-packages/setuptools']

<module>.__file__ lets you identify the location of a specific module: (difference)
```
  $ python3 -c "import os as _; print(_.__file__)"
  /usr/lib/python3.6/os.py
```

Run pip show <package> to show Debian-style package information:

  $ pip show pytest
  Name: pytest
  Version: 3.8.2
  Summary: pytest: simple powerful testing with Python
  Home-page: https://docs.pytest.org/en/latest/
  Author: Holger Krekel, Bruno Oliveira, Ronny Pfannschmidt, Floris Bruynooghe, Brianna Laugher, Florian Bruhin and others
  Author-email: None
  License: MIT license
  Location: /home/peter/.local/lib/python3.4/site-packages
  Requires: more-itertools, atomicwrites, setuptools, attrs, pathlib2, six, py, pluggy

How do I find the location of Python module sources while I can not import it?

Try:

import imp
imp.find_module('cv2')

Where are python modules stored?

Suppose you want to know the location of xyz module. You do this on the interpreter

>>> import xyx
>>> xyz.__file__

You'll get the location of the pyc file from where your module is being imported.

You can also simply do

>>> xyz

to get the module name and the location of the module.

To know about all the possible locations from where the modules are imported, use sys.path:

>>> import sys
>>> sys.path

This will give you the list of the locations where Python searches for a module when you do import.

Hope that helps.

is there a way to view the source of a module from within the python console?

Some of the methods of inspect module are well-suited for this purpose:

import module
import inspect
src = inspect.getsource(module)

How can I find the location of the source code of a built-in Python method?

You can usually find the source files for core python modules in the python installation folder itself. For instance, on linux, I can find the source code for os module which is a quite popular python module in this location:

/usr/lib/python2.7/os.py

If you are on windows, this is generally C:\python27\lib, but you can verify it for yourself by running which python in case of linux and where python in case of windows.

how to get module location

It is worth mentioning that packages have __file__ attribute which points to __init__.py, they also have __path__ which points to the package directory. So you can use hasattr(module_name, '__path__') and module_name.__path__[0] or module_name.__file__.

Example (in REPL):

import socket, SOAPpy # SOAPpy is a package
socket.__file__
# .../python2.5/socket.pyc
socket.__path__
# AttributeError: 'module' object has no attribute '__path__'
SOAPpy.__file__
# .../2.5/site-packages/SOAPpy/__init__.pyc
SOAPpy.__path__
# ['.../2.5/site-packages/SOAPpy']