Packaging and Distributing Projects

Page Status:Complete
Last Reviewed:2014-12-31

This section covers the basics of how to configure, package and distribute your own Python projects. It assumes that you are already familiar with the contents of the Installing Packages.

The section does not aim to cover best practices for Python project development as a whole. For example, it does not provide guidance or tool recommendations for version control, documentation, or testing.

For more reference material, see Building and Distributing Packages in the setuptools docs, but note that some advisory content there may be outdated. In the event of conflicts, prefer the advice in the Python Packaging User Guide.

Requirements for Packaging and Distributing

  1. First, make sure you have already fulfilled the requirements for installing packages.

  2. Install “wheel” [1]:

    pip install wheel

    You’ll need this to package your project into wheels (see below).

  3. Install “twine” [1]:

    pip install twine

    You’ll need this to upload your project distributions to PyPI (see below).

Configuring your Project

Initial Files

The most important file is “” which exists at the root of your project directory. For an example, see the in the PyPA sample project.

“” serves two primary functions:

  1. It’s the file where various aspects of your project are configured. The primary feature of is that it contains a global setup() function. The keyword arguments to this function are how specific details of your project are defined. The most relevant arguments are explained in the section below.
  2. It’s the command line interface for running various commands that relate to packaging tasks. To get a listing of available commands, run python --help-commands.


“setup.cfg” is an ini file that contains option defaults for commands. For an example, see the setup.cfg in the PyPA sample project.


All projects should contain a readme file that covers the goal of the project. The most common format is reStructuredText with an “rst” extension, although this is not a requirement.

For an example, see README.rst from the PyPA sample project

A “” is needed in certain cases where you need to package additional files that python sdist (or bdist_wheel) don’t automatically include. To see a list of what’s included by default, see the Specifying the files to distribute section from the distutils documentation.

For an example, see the from the PyPA sample project

For details on writing a file, see the The template section from the distutils documentation.

<your package>

Although it’s not required, the most common practice to is to include your python modules and packages under a single top-level package that has the same name as your project, or something very close.

For an example, see the sample package that’s include in the PyPA sample project

setup() args

As mentioned above, The primary feature of is that it contains a global setup() function. The keyword arguments to this function are how specific details of your project are defined.

The most relevant arguments are explained below. The snippets given are taken from the contained in the PyPA sample project.



This is the name of your project, and will determine how your project is listed on PyPI. For details on permitted characters, see the name section from PEP426.



Projects should comply with the version scheme specified in PEP440. Here are some examples:

1.2.0.dev1  # Development release
1.2.0a1     # Alpha Release
1.2.0b1     # Beta Release
1.2.0rc1    # RC Release
1.2.0       # Final Release
1.2.0.post1 # Post Release

If the project code itself needs run-time access to the version, the simplest way is to keep the version in both and your code. If you’d rather not duplicate the value, there are a few ways to manage this. See the “Single-sourcing the Project Version” Advanced Topics section.


description='A sample Python project',

Give a short and long description for you project. These values will be displayed on PyPI if you publish your project.



Give a homepage url for your project.


author='The Python Packaging Authority',

Provide details about the author.



Provide the type of license you are using.


    # How mature is this project? Common values are
    #   3 - Alpha
    #   4 - Beta
    #   5 - Production/Stable
    'Development Status :: 3 - Alpha',

    # Indicate who your project is intended for
    'Intended Audience :: Developers',
    'Topic :: Software Development :: Build Tools',

    # Pick your license as you wish (should match "license" above)
     'License :: OSI Approved :: MIT License',

    # Specify the Python versions you support here. In particular, ensure
    # that you indicate whether you support Python 2, Python 3 or both.
    'Programming Language :: Python :: 2',
    'Programming Language :: Python :: 2.6',
    'Programming Language :: Python :: 2.7',
    'Programming Language :: Python :: 3',
    'Programming Language :: Python :: 3.2',
    'Programming Language :: Python :: 3.3',
    'Programming Language :: Python :: 3.4',

Provide a list of classifiers the categorize your project. For a full listing, see


keywords='sample setuptools development',

List keywords that describe your project.


packages=find_packages(exclude=['contrib', 'docs', 'tests*']),

It’s required to list the packages to be included in your project. Although they can be listed manually, setuptools.find_packages finds them automatically. Use the exclude keyword argument to omit packages that are not intended to be released and installed.



“install_requires” should be used to specify what dependencies a project minimally needs to run. When the project is installed by pip, this is the specification that is used to install its dependencies.

For more on using “install_requires” see install_requires vs Requirements files.


    'sample': ['package_data.dat'],

Often, additional files need to be installed into a package. These files are often data that’s closely related to the package’s implementation, or text files containing documentation that might be of interest to programmers using the package. These files are called “package data”.

The value must be a mapping from package name to a list of relative path names that should be copied into the package. The paths are interpreted as relative to the directory containing the package.

For more information, see Including Data Files from the setuptools docs.


data_files=[('my_data', ['data/data_file'])],

Although configuring package_data is sufficient for most needs, in some cases you may need to place data files outside of your packages. The data_files directive allows you to do that.

Each (directory, files) pair in the sequence specifies the installation directory and the files to install there. If directory is a relative path, it is interpreted relative to the installation prefix (Python’s sys.prefix for pure-Python distributions, sys.exec_prefix for distributions that contain extension modules). Each file name in files is interpreted relative to the script at the top of the project source distribution.

For more information see the distutils section on Installing Additional Files.


setuptools allows absolute “data_files” paths, and pip honors them as absolute, when installing from sdist. This is not true when installing from wheel distributions. Wheels don’t support absolute paths, and they end up being installed relative to “site-packages”. For discussion see wheel Issue #92.


Although setup() supports a scripts keyword for pointing to pre-made scripts to install, the recommended approach to achieve cross-platform compatibility is to use console_scripts entry points (see below).



Use this keyword to specify any plugins that your project provides for any named entry points that may be defined by your project or others that you depend on.

For more information, see the section on Dynamic Discovery of Services and Plugins from the setuptools docs.

The most commonly used entry point is “console_scripts” (see below).

    'console_scripts': [

Use “console_script” entry points to register your script interfaces. You can then let the toolchain handle the work of turning these interfaces into actual scripts [2]. The scripts will be generated during the install of your distribution.

For more information, see Automatic Script Creation from the setuptools docs.

Working in “Development Mode”

Although not required, it’s common to locally install your project in “develop” or “editable” mode while you’re working on it. This allows the project to be both installed and editable in project form.

Using “”, run the following:

python develop

Or you can achieve the same result using pip:

pip install -e .

Note that both commands will install any dependencies declared with “install_requires” and also any scripts declared with “console_scripts”.

For more information, see the Development Mode section of the setuptools docs.

Packaging your Project

To have your project installable from a Package Index like PyPI, you’ll need to create a Distribution (aka “Package” ) for your project.

Source Distributions

Minimally, you should create a Source Distribution:

python sdist

A “source distribution” is unbuilt (i.e, it’s not a Built Distribution), and requires a build step when installed by pip. Even if the distribution is pure python (i.e. contains no extensions), it still involves a build step to build out the installation metadata from


You should also create a wheel for your project. A wheel is a built package that can be installed without needing to go through the “build” process. Installing wheels is substantially faster for the end user than installing from a source distribution.

If your project is pure python (i.e. contains no compiled extensions) and natively supports both Python 2 and 3, then you’ll be creating what’s called a “Universal Wheel” (see section below).

If your project is pure python but does not natively support both Python 2 and 3, then you’ll be creating a “Pure Python Wheel” (see section below).

If you project contains compiled extensions, then you’ll be creating what’s called a “Platform Wheel” (see section below).

Universal Wheels

“Universal Wheels” are wheels that are pure python (i.e. contains no compiled extensions) and support Python 2 and 3. This is a wheel that can be installed anywhere by pip.

To build a Universal Wheel:

python bdist_wheel --universal

You can also permanently set the --universal flag in “setup.cfg” (e.g., see sampleproject/setup.cfg)


Only use the --universal setting, if:

  1. Your project runs on Python 2 and 3 with no changes (i.e. it does not require 2to3).
  2. Your project does not have any C extensions.

Beware that bdist_wheel does not currently have any checks to warn you if use the setting inappropriately.

If your project has optional C extensions, it is recommended not to publish a universal wheel, because pip will prefer the wheel over a source installation, and prevent the possibility of building the extension.

Pure Python Wheels

“Pure Python Wheels” that are not “universal” are wheels that are pure python (i.e. contains no compiled extensions), but don’t natively support both Python 2 and 3.

To build the wheel:

python bdist_wheel

bdist_wheel will detect that the code is pure Python, and build a wheel that’s named such that it’s usable on any Python installation with the same major version (Python 2 or Python 3) as the version you used to build the wheel. For details on the naming of wheel files, see PEP425

If your code supports both Python 2 and 3, but with different code (e.g., you use “2to3”) you can run bdist_wheel twice, once with Python 2 and once with Python 3. This will produce wheels for each version.

Platform Wheels

“Platform Wheels” are wheels that are specific to a certain platform like linux, OSX, or Windows, usually due to containing compiled extensions.

To build the wheel:

python bdist_wheel

bdist_wheel will detect that the code is not pure Python, and build a wheel that’s named such that it’s only usable on the platform that it was built on. For details on the naming of wheel files, see PEP425


PyPI currently only allows uploads of platform wheels for Windows and OS X, NOT linux. Currently, the wheel tag specification (PEP425) does not handle the variation that can exist across linux distros.

Uploading your Project to PyPI


Before releasing on main PyPI repo, you might prefer training with PyPI test site which is cleaned on a semi regular basis. See these instructions on how to setup your configuration in order to use it.

Create an account

First, you need a PyPI user account. There are two options:

  1. Create an account manually using the form on the PyPI website.
  2. Have an account created as part of registering your first project (see option #2 below).

Register your project

Next, you need to register your project. There are two ways to do this:

  1. (Recommended): Use the form on the PyPI website. Although the form is cumbersome, it’s a secure option over using #2 below, which passes your credentials over plaintext.
  2. Run python register. If you don’t have a user account already, a wizard will create one for you.

If you created your account using option #1 (the form), you’ll need to manually write a ~/.pypirc file like so.


repository =
username = <username>
password = <password>

You can leave out the password line if below you use twine with its -p PASSWORD argument.

Upload your distributions

Finally, you can upload your distributions to PyPI.

There are two options:

  1. (Recommended): Use twine

    twine upload dist/*

    The biggest reason to use twine is that python upload (option #2 below) uploads files over plaintext. This means anytime you use it you expose your username and password to a MITM attack. Twine uses only verified TLS to upload to PyPI protecting your credentials from theft.

    Secondly it allows you to precreate your distribution files. python upload only allows you to upload something that you’ve created in the same command invocation. This means that you cannot test the exact file you’re going to upload to PyPI to ensure that it works before uploading it.

    Finally it allows you to pre-sign your files and pass the .asc files into the command line invocation (twine upload twine-1.0.1.tar.gz twine-1.0.1.tar.gz.asc). This enables you to be assured that you’re typing your gpg passphrase into gpg itself and not anything else since you will be the one directly executing gpg --detach-sign -a <filename>.

  2. Use setuptools:

    python sdist bdist_wheel upload

[1](1, 2) Depending on your platform, this may require root or Administrator access. pip is currently considering changing this by making user installs the default behavior.
[2]Specifically, the “console_script” approach generates .exe files on Windows, which are necessary because the OS special-cases .exe files. Script-execution features like PATHEXT and the Python Launcher for Windows allow scripts to be used in many cases, but not all.