Merged revisions 83675 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/branches/py3k

........
  r83675 | r.david.murray | 2010-08-03 13:56:09 -0400 (Tue, 03 Aug 2010) | 12 lines

  #9444: use first of prefix_chars for help opt instead of raising error

  An argparse option parser created with a prefix_chars that did not
  include a '-' would happily add -h and --help options, and then throw
  an error when it tried to format the help because the - was an invalid
  prefix character.  This patch makes it use the first character of
  prefix_chars as the character for the help options if and only if '-'
  is not one of the valid prefix_chars.

  Fix by Theodore Turocy, unit tests by Catherine Devlin.
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diff --git a/Misc/NEWS b/Misc/NEWS
index 323b0a3..431c3d5 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -24,6 +24,10 @@
 Library
 -------
 
+- Issue #9444: Argparse now uses the first element of prefix_chars as
+  the option character for the added 'h/help' option if prefix_chars
+  does not contain a '-', instead of raising an error.
+
 - Issue #9354: Provide getsockopt() in asyncore's file_wrapper.
 
 - Issue #7781: Fix restricting stats by entry counts in the pstats