Specific versions of the Python runtime can be specified with a `runtime.txt` file:
Specific versions of the Python runtime can be specified with a `runtime.txt` file:
$ cat runtime.txt
$ cat runtime.txt
python-3.5.1
python-3.5.2
Runtime options include:
Runtime options include:
-`python-2.7.11`
-`python-2.7.12`
-`python-3.5.1`
-`python-3.5.2`
-`pypy-5.0.1` (unsupported, experimental)
-`pypy-5.3.1` (unsupported, experimental)
Other [unsupported runtimes](https://github.com/heroku/heroku-buildpack-python/tree/master/builds/runtimes) are available as well. Use at your own risk.
Other [unsupported runtimes](https://github.com/heroku/heroku-buildpack-python/tree/master/builds/runtimes) are available as well. Use at your own risk.