--- C:/Python31/Lib/string.py	Wed Feb 17 17:21:02 2010
+++ C:/Python31/Lib/string.py	Sat Jul 10 17:42:57 2010
@@ -188,6 +188,39 @@
                              self.pattern)
         return self.pattern.sub(convert, self.template)
 
+    def from_template(self, *args, **kws):
+        if len(args) > 1:
+            raise TypeError('Too many positional arguments')
+        if not args:
+            mapping = kws
+        elif kws:
+            mapping = _multimap(kws, args[0])
+        else:
+            mapping = args[0]
+        # Helper function for .sub()
+        def convert(mo):
+            named = mo.group('named')
+            if named is not None:
+                try:
+                    # We use this idiom instead of str() because the latter
+                    # will fail if val is a Unicode containing non-ASCII
+                    return '%s' % (mapping[named],)
+                except KeyError:
+                    return self.delimiter + named
+            braced = mo.group('braced')
+            if braced is not None:
+                try:
+                    return '%s' % (mapping[braced],)
+                except KeyError:
+                    return self.delimiter + '{' + braced + '}'
+            if mo.group('escaped') is not None:
+                return self.delimiter + self.delimiter
+            if mo.group('invalid') is not None:
+                return self.delimiter
+            raise ValueError('Unrecognized named group in pattern',
+                             self.pattern)
+        return Template(self.pattern.sub(convert, self.template))
+
 
 
 ########################################################################