From the official guide:
“This optional entry at the end of the effects has #restricted as the cell entry. This means that the policy is not available to all policies but only the ones whose object names (not GUINames) are listed in the cells after this in a line. You can have just one entry, several or none, and the #restricted cell is entirely optional.”
I don’t get this, what means restrict policies from other policies? Or it is an error in the guide and the restricted function serves to restrict policy to certain countries? That’s would make more sense.