checking for `--check` inside callback module

Hi I am creating a custom callback module and I want it to have different behavior when in check mode. However I have not found a way to detect this, is there a way for me to tell as a callback plugin if we are running in check mode?
The goal is to only run this module when --check is enabled.

nevermind, found it https://groups.google.com/forum/#!searchin/ansible-devel/check$20mode|sort:relevance/ansible-devel/41dc3EnZ7eM/le03tWvBBQAJ