Bug fix for #780461: 'sysu' gestalt selector is meaningless on MacOSX,
but attempting to get it resulted in a crash. Fixed. Backport candidate.
diff --git a/Lib/platform.py b/Lib/platform.py
index 9404b5c..1547e12 100755
--- a/Lib/platform.py
+++ b/Lib/platform.py
@@ -525,12 +525,13 @@
 def _mac_ver_lookup(selectors,default=None):
 
     from gestalt import gestalt
+    import MacOS
     l = []
     append = l.append
     for selector in selectors:
         try:
             append(gestalt(selector))
-        except RuntimeError:
+        except (RuntimeError, MacOS.Error):
             append(default)
     return l
 
@@ -557,6 +558,7 @@
     # Check whether the version info module is available
     try:
         import gestalt
+        import MacOS
     except ImportError:
         return release,versioninfo,machine
     # Get the infos