Issue #1766304:  Optimize membership testing for ranges:  'n in range(...)'
does an O(1) check, if n is an integer.  Non-integers aren't affected.
Thanks Robert Lehmann.
diff --git a/Misc/NEWS b/Misc/NEWS
index 4e49d8f..4b8ad74 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,8 @@
 Core and Builtins
 -----------------
 
+- Issue #1766304: Improve performance of membership tests on range objects.
+
 - Issue #6713: Improve performance of integer -> string conversions.
 
 - Issue #6846: Fix bug where bytearray.pop() returns negative integers.