Issue #17047: remove doubled words found in 2.7 to 3.4 Modules/*,
as reported by Serhiy Storchaka and Matthew Barnett.
diff --git a/Modules/zlib/inftrees.h b/Modules/zlib/inftrees.h
index baa53a0..24230c5 100644
--- a/Modules/zlib/inftrees.h
+++ b/Modules/zlib/inftrees.h
@@ -41,7 +41,7 @@
    examples/enough.c found in the zlib distribtution.  The arguments to that
    program are the number of symbols, the initial root table size, and the
    maximum bit length of a code.  "enough 286 9 15" for literal/length codes
-   returns returns 852, and "enough 30 6 15" for distance codes returns 592.
+   returns 852, and "enough 30 6 15" for distance codes returns 592.
    The initial root table size (9 or 6) is found in the fifth argument of the
    inflate_table() calls in inflate.c and infback.c.  If the root table size is
    changed, then these maximum sizes would be need to be recalculated and