[ccp4bb] PyMOL question

[L. Doyle]

Hello!
Does anyone know how to select residues in object 1 that are different from 
object 2? I know how to select residues that are similar ("select name, obj1 
like obj2") but can't figure out how to do the opposite. I am running PyMOL on 
a Mac.
Thank you,
Lindsey