Merged revisions 85930 via svnmerge from
http://svn.python.org/projects/python/branches/py3k

........
  r85930 | alexander.belopolsky | 2010-10-29 13:16:49 -0400 (Fri, 29 Oct 2010) | 1 line

  Issue 7061: Explained 'gon'
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diff --git a/Lib/lib-tk/turtle.py b/Lib/lib-tk/turtle.py
index 90dadf9..23e407d 100644
--- a/Lib/lib-tk/turtle.py
+++ b/Lib/lib-tk/turtle.py
@@ -1495,7 +1495,10 @@
         >>> turtle.left(90)
         >>> turtle.heading()
         90
-        >>> turtle.degrees(400.0)  # angle measurement in gon
+
+        Change angle measurement unit to grad (also known as gon,
+        grade, or gradian and equals 1/100-th of the right angle.)
+        >>> turtle.degrees(400.0)
         >>> turtle.heading()
         100