Issue #17047: remove doubled words found in 2.7 to 3.4 Lib/*,
as reported by Serhiy Storchaka and Matthew Barnett.
diff --git a/Lib/lib-tk/turtle.py b/Lib/lib-tk/turtle.py
index aa4fe84..2954051 100644
--- a/Lib/lib-tk/turtle.py
+++ b/Lib/lib-tk/turtle.py
@@ -811,8 +811,8 @@
 class Terminator (Exception):
     """Will be raised in TurtleScreen.update, if _RUNNING becomes False.
 
-    Thus stops execution of turtle graphics script. Main purpose: use in
-    in the Demo-Viewer turtle.Demo.py.
+    This stops execution of a turtle graphics script.
+    Main purpose: use in the Demo-Viewer turtle.Demo.py.
     """
     pass