Fix the NamespaceFormatter example in PEP 3101.

pep-3101.txt

@@ -595,9 +595,9 @@ Customizing Formatters
               if isinstance(key, str):
                   try:
                       # Check explicitly passed arguments first
-                      return kwds[name]
+                      return kwds[key]
                   except KeyError:
-                      return self.namespace[name]
+                      return self.namespace[key]
               else:
                   Formatter.get_value(key, args, kwds)
 
@@ -607,7 +607,7 @@ Customizing Formatters
         fmt = NamespaceFormatter(globals())
 
         greeting = "hello"
-        print(fmt("{greeting}, world!"))
+        print(fmt.format("{greeting}, world!"))
 
     A similar technique can be done with the locals() dictionary to
     gain access to the locals dictionary.