Is there a standard way to list names of Python modules in a package?


Python Problem Overview

Is there a straightforward way to list the names of all modules in a package, without using __all__?

For example, given this package:


I'm wondering if there is a standard or built-in way to do something like this:

>>> package_contents("testpkg")
['modulea', 'moduleb']

The manual approach would be to iterate through the module search paths in order to find the package's directory. One could then list all the files in that directory, filter out the uniquely-named py/pyc/pyo files, strip the extensions, and return that list. But this seems like a fair amount of work for something the module import mechanism is already doing internally. Is that functionality exposed anywhere?

Python Solutions

Solution 1 - Python

Using python2.3 and above, you could also use the pkgutil module:

>>> import pkgutil
>>> [name for _, name, _ in pkgutil.iter_modules(['testpkg'])]
['modulea', 'moduleb']

EDIT: Note that the parameter for pkgutil.iter_modules is not a list of modules, but a list of paths, so you might want to do something like this:

>>> import os.path, pkgutil
>>> import testpkg
>>> pkgpath = os.path.dirname(testpkg.__file__)
>>> print([name for _, name, _ in pkgutil.iter_modules([pkgpath])])

Solution 2 - Python

import module

Solution 3 - Python

Maybe this will do what you're looking for?

import imp
import os
MODULE_EXTENSIONS = ('.py', '.pyc', '.pyo')

def package_contents(package_name):
    file, pathname, description = imp.find_module(package_name)
    if file:
        raise ImportError('Not a package: %r', package_name)
    # Use a set because some may be both source and compiled.
    return set([os.path.splitext(module)[0]
        for module in os.listdir(pathname)
        if module.endswith(MODULE_EXTENSIONS)])

Solution 4 - Python

Don't know if I'm overlooking something, or if the answers are just out-dated but;

As stated by user815423426 this only works for live objects and the listed modules are only modules that were imported before.

Listing modules in a package seems really easy using inspect:

>>> import inspect, testpkg
>>> inspect.getmembers(testpkg, inspect.ismodule)
['modulea', 'moduleb']

Solution 5 - Python

This is a recursive version that works with python 3.6 and above:

import importlib.util
from pathlib import Path
import os

def package_contents(package_name):
    spec = importlib.util.find_spec(package_name)
    if spec is None:
        return set()
    pathname = Path(spec.origin).parent
    ret = set()
    with os.scandir(pathname) as entries:
        for entry in entries:
            current = '.'.join((package_name,'.')[0]))
            if entry.is_file():
            elif entry.is_dir():
                ret |= package_contents(current)
    return ret

Solution 6 - Python

This should list the modules:


Solution 7 - Python

Based on cdleary's example, here's a recursive version listing path for all submodules:

import imp, os

def iter_submodules(package):
    file, pathname, description = imp.find_module(package)
    for dirpath, _, filenames in os.walk(pathname):
        for  filename in filenames:
            if os.path.splitext(filename)[1] == ".py":
                yield os.path.join(dirpath, filename)

Solution 8 - Python

If you would like to view an inforamtion about your package outside of the python code (from a command prompt) you can use pydoc for it.

# get a full list of packages that you have installed on you machine
$ python -m pydoc modules

# get information about a specific package
$ python -m pydoc <your package>

You will have the same result as pydoc but inside of interpreter using help

>>> import <my package>
>>> help(<my package>)

Solution 9 - Python

The other answers here will run the code in the package as they inspect it. If you don't want that, you can grep the files like this answer

def _get_class_names(file_name: str) -> List[str]:
    """Get the python class name defined in a file without running code
    file_name: the name of the file to search for class definitions in
    return: all the classes defined in that python file, empty list if no matches"""
    defined_class_names = []
    # search the file for class definitions
    with open(file_name, "r") as file:
        for line in file:
            # regular expression for class defined in the file
            # searches for text that starts with "class" and ends with ( or :,
            # whichever comes first
            match ="^class(.+?)(\(|:)", line) # noqa
            if match:
                # add the cleaned match to the list if there is one
                defined_class_name =
    return defined_class_names

Solution 10 - Python

def package_contents(package_name):
  package = __import__(package_name)
  return [module_name for module_name in dir(package) if not module_name.startswith("__")]


All content for this solution is sourced from the original question on Stackoverflow.

The content on this page is licensed under the Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license.

Content TypeOriginal AuthorOriginal Content on Stackoverflow
QuestionDNSView Question on Stackoverflow
Solution 1 - Pythonjp.View Answer on Stackoverflow
Solution 2 - PythonKenan BanksView Answer on Stackoverflow
Solution 3 - PythoncdlearyView Answer on Stackoverflow
Solution 4 - Pythonsiebz0rView Answer on Stackoverflow
Solution 5 - PythontacaswellView Answer on Stackoverflow
Solution 6 - PythonAmmonView Answer on Stackoverflow
Solution 7 - PythonVajk HermeczView Answer on Stackoverflow
Solution 8 - PythonVlad BezdenView Answer on Stackoverflow
Solution 9 - Pythonjsmith2021View Answer on Stackoverflow
Solution 10 - Pythonjr View Answer on Stackoverflow