How to close render using python API?

I created a unity environment and trying to train using python API. In order to speed up, I'd like to close the render unity environment, but haven't found any methods in python API.

Run this
mlagents-learn --help

--no-graphics Whether to run the Unity executable in no-graphics
mode (i.e. without initializing the graphics driver.
Use this only if your agents don't use visual
observations. (default: False)

Note: Requires compiled executable of the Unity Environment