SF 563203. Replaced 'has_key()' with 'in'.
diff --git a/Lib/SimpleHTTPServer.py b/Lib/SimpleHTTPServer.py
index 2caa89d..f8e3fc5 100644
--- a/Lib/SimpleHTTPServer.py
+++ b/Lib/SimpleHTTPServer.py
@@ -175,10 +175,10 @@
         """
 
         base, ext = posixpath.splitext(path)
-        if self.extensions_map.has_key(ext):
+        if ext in self.extensions_map:
             return self.extensions_map[ext]
         ext = ext.lower()
-        if self.extensions_map.has_key(ext):
+        if ext in self.extensions_map:
             return self.extensions_map[ext]
         else:
             return self.extensions_map['']