https://bugs.gentoo.org/952478
https://github.com/pychess/pychess/issues/2233
https://github.com/pychess/pychess/commit/8d8431c3e8023adbdffea9782b6f2370bb367673
--- a/lib/pychess/ic/TimeSeal.py
+++ b/lib/pychess/ic/TimeSeal.py
@@ -2,3 +2,2 @@
 import sys
-import telnetlib
 import random
@@ -25,3 +24,5 @@
 FILLER = b"1234567890abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
-IAC_WONT_ECHO = b"".join([telnetlib.IAC, telnetlib.WONT, telnetlib.ECHO])
+# was: b"".join([telnetlib.IAC, telnetlib.WONT, telnetlib.ECHO])
+# but telnetlib was removed in Python 3.13
+IAC_WONT_ECHO = b"\xff\xfc\x01"