Specifying a Python 2 environment with runtime.txt

We can specify various runtime parameters with a runtime.txt file. In this repository, we demonstrate how to install python 2 with the environment.

If you specify python-2.7 in runtime.txt, then:

• A python3 environment is created & installed (this is what the notebook runs from)
• A python2 environment is created and registered
• The contents of requirements.txt are installed into the python2 environment

important: Make sure that you save your notebooks with a python 2 kernel activated, as this defines which kernel Binder will use when a notebook is opened.

note: If you also wish to install python 3 dependencies, you may do so by including a file called requirements3.txt. The packages inside will be installed into the python 3 environment.