[Chimera-users] Command line for labelling specific residues in a zone

I am not sure if this request was missed. I am having difficulty finding the syntax to write a line command in Chimera to label the non-polar or polar residues in say a 5 Angstroms zone. I would be grateful if you could advise me how to code the command line for labelling these residues with a 1-letter code please ? Once I see the format then I can readily adapt this to other situations. Thank you in advance. Mark