How to create a group restricted cart rule with PHP ?

[masterblaster]

I need to create a group restricted CartRule in a PHP script I am building that it is interacting with PS 1.6 database ,

but I can't find a way to assign the rule to some restricted customer groups.

 

I see that the CartRule object have a boolean $group_restriction variable 

but I can't really figure out how to fill up the "ps_cart_rule_group"

with groups of my interest  by using Prestashop code to the CartRule I just created.

 

Any advice ?

 

Thank you.