# Heroku Buildpack: Python
![buildpack_python](https://cloud.githubusercontent.com/assets/51578/13116296/5f4058f0-d569-11e5-8129-bffd7be091e6.jpg)

This is a [Heroku buildpack](http://devcenter.heroku.com/articles/buildpacks) for Python apps, powered by [pip](http://www.pip-installer.org/).

This buildpack supports running Django and Flask apps.


Usage
-----

Example usage:

    $ ls
    Procfile  requirements.txt  web.py

    $ heroku create --buildpack git://github.com/heroku/heroku-buildpack-python.git

    $ git push heroku master
    ...
    -----> Python app detected
    -----> Installing python-2.7.11
         $ pip install -r requirements.txt
           Downloading/unpacking requests (from -r requirements.txt (line 1))
           Installing collected packages: requests
           Successfully installed requests
           Cleaning up...
    -----> Discovering process types
           Procfile declares types -> (none)

You can also add it to upcoming builds of an existing application:

    $ heroku buildpacks:set heroku/python

The buildpack will detect your app as Python if it has the file `requirements.txt` in the root.

It will use pip to install your dependencies, vendoring a copy of the Python runtime into your slug.

Specify a Runtime
-----------------

You can also specify specific versions of the Python runtime with a `runtime.txt` file:

    $ cat runtime.txt
    python-3.5.1

Runtime options include:

- `python-2.7.11`
- `python-3.5.1`
- `pypy-4.0.1` (unsupported, experimental)
- `pypy3-2.4.0` (unsupported, experimental)

Other [unsupported runtimes](https://github.com/heroku/heroku-buildpack-python/tree/master/builds/runtimes) are available as well.