Issue #5341: Fix a variety of spelling errors.
diff --git a/Lib/test/test_codeccallbacks.py b/Lib/test/test_codeccallbacks.py
index db0bc96..dfd12e5 100644
--- a/Lib/test/test_codeccallbacks.py
+++ b/Lib/test/test_codeccallbacks.py
@@ -109,7 +109,7 @@
         # useful that the error handler is not called for every single
         # unencodable character, but for a complete sequence of
         # unencodable characters, otherwise we would output many
-        # unneccessary escape sequences.
+        # unnecessary escape sequences.
 
         def uninamereplace(exc):
             if not isinstance(exc, UnicodeEncodeError):