releaseLicense()
When you import the hou module into a Python shell, it will acquire a Houdini license. This function exists so you can release that license when you're done using the hou module. This way, you can have a long running Python script that periodically uses Houdini without having to hold a Houdini license for the entire duration of the script.
After you release the license, it will automatically be reacquired when you access functions and objects from the hou module.