one of the documented procedures in this installation of the ACS
edu_action_to_pretty_roles   db   group_id   action
What it does:
This takes an action and returns a string of roles that can perform that action.
Defined in: /web/philip/tcl/education.tcl

Source code:

    if {[empty_string_p $action]} {
	return Public
    } else {
	set roles_list [database_to_tcl_list $db "select pretty_role 
              from user_group_action_role_map ugmap,
                   edu_role_pretty_role_map role_map
             where group_id = $group_id 
               and action = '$action'
               and ugmap.role = role_map.role
      order by sort_key"]
	return [join $roles_list ", "]