The module github_key was not found in configured module paths

I am trying to get this working and am using the example on the docs, but getting the error “The module github_key was not found in configured module paths. Additionally, core modules are missing. If this is a checkout, run ‘git submodule update --init --recursive’ to correct this problem.” I installed ansible via homebrew.

github_key is labeled as “New in version 2.2.”

The current stable version of ansible is 2.1.2.0.

Ansible 2.2 is in RC1 currently, and you can find information about it at https://groups.google.com/forum/#!topic/ansible-devel/Ca07JSmyxIQ