Make use of new str.startswith/endswith semantics.
Occurences in email and compiler were ignored due to backwards compat requirements.
diff --git a/Lib/trace.py b/Lib/trace.py
index ca6294e..db36e1d 100644
--- a/Lib/trace.py
+++ b/Lib/trace.py
@@ -285,7 +285,7 @@
             if filename == "<string>":
                 continue
 
-            if filename.endswith(".pyc") or filename.endswith(".pyo"):
+            if filename.endswith((".pyc", ".pyo")):
                 filename = filename[:-1]
 
             if coverdir is None: