Probably.  PEPs, once completed (unless they are informational PEPs), are historical documents, and the real implementation may diverge from the PEP immediately, or after maintenance updates.  The real documentation for the added feature should be in the main docs.  We are not always good about making that true, and we do reference the PEPs, and so sometimes we do update them.  I'll leave this open so someone knowledgeable about it can decide if this should be fixed, or if there are missing "real docs" (I don't get hits for either constant grepping the docs).