Calling the "Add Item" button via script in Product Class-UI Option-Group Items

Hello Experts, 

Customer would like to call the "Add Item" button via script to add attributes as UI Option Group Items under product classes. ie simulate the result of the following actions:

1. Navigate to Administration-Product->Product Classes
2. Create a new product class and add several attributes (Attribute Definitions) to this class
3. Go inside the "workspace" version of the product class and click on the "User Interface" tab
4. Create a new UI Option record ("New" button) with any theme
5. Drilldown into this newly created UI Option record
6. Create a new UI Group record in the middle applet (using "New" button) with any theme and highlight/select this newly created record