What does code P0141 "post cat 02 sensor heater performance fault" mean on 2000 Chevrolet Cavalier

This is what came back from my engine light coming on and being diagnosed.

Asked by for the 2000 Chevrolet Cavalier
for the po141.
Replace oxygen sensor (cannot repair open or short that occurs internally to sensor).
Repair short or open or high resistance in wiring harness or harness connectors.