Merged revisions 83226-83227,83229-83232 via svnmerge from
svn+ssh://svn.python.org/python/branches/py3k

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  r83226 | georg.brandl | 2010-07-29 16:17:12 +0200 (Do, 29 Jul 2010) | 1 line

  #1090076: explain the behavior of *vars* in get() better.
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  r83227 | georg.brandl | 2010-07-29 16:23:06 +0200 (Do, 29 Jul 2010) | 1 line

  Use Py_CLEAR().
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  r83229 | georg.brandl | 2010-07-29 16:32:22 +0200 (Do, 29 Jul 2010) | 1 line

  #9407: document configparser.Error.
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  r83230 | georg.brandl | 2010-07-29 16:36:11 +0200 (Do, 29 Jul 2010) | 1 line

  Use correct directive and name.
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  r83231 | georg.brandl | 2010-07-29 16:46:07 +0200 (Do, 29 Jul 2010) | 1 line

  #9397: remove mention of dbm.bsd which does not exist anymore.
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  r83232 | georg.brandl | 2010-07-29 16:49:08 +0200 (Do, 29 Jul 2010) | 1 line

  #9388: remove ERA_YEAR which is never defined in the source code.
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diff --git a/Lib/configparser.py b/Lib/configparser.py
index bfbe4cb..14ddd85 100644
--- a/Lib/configparser.py
+++ b/Lib/configparser.py
@@ -521,11 +521,12 @@
     def get(self, section, option, raw=False, vars=None):
         """Get an option value for a given section.
 
-        All % interpolations are expanded in the return values, based on the
-        defaults passed into the constructor, unless the optional argument
-        `raw' is true.  Additional substitutions may be provided using the
-        `vars' argument, which must be a dictionary whose contents overrides
-        any pre-existing defaults.
+        If `vars' is provided, it must be a dictionary. The option is looked up
+        in `vars' (if provided), `section', and in `defaults' in that order.
+
+        All % interpolations are expanded in the return values, unless the
+        optional argument `raw' is true.  Values for interpolation keys are
+        looked up in the same manner as the option.
 
         The section DEFAULT is special.
         """