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diff --git a/ACE/bin/PythonACE/fuzz/_singleton.py b/ACE/bin/PythonACE/fuzz/_singleton.py
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+++ b/ACE/bin/PythonACE/fuzz/_singleton.py
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+""" Implements a singleton mixin class """
+
+# The following code was written by Gary Robinson
+# (grobinson@transpose.com) and placed in the public domain.  His
+# copyright notice is as follows:
+
+# By Gary Robinson, grobinson@transpose.com. No rights reserved -- 
+# placed in the public domain -- which is only reasonable considering
+# how much it owes to other people's version which are in the
+# public domain. The idea of using a metaclass came from 
+# a  comment on Gary's blog (see 
+# http://www.garyrobinson.net/2004/03/python_singleto.html#comments). 
+# Other improvements came from comments and email from other
+# people who saw it online. (See the blog post and comments
+# for further credits.)
+
+# Not guaranteed to be fit for any particular purpose. Use at your
+# own risk.
+
+
+class SingletonException(Exception):
+    pass
+
+class MetaSingleton(type):
+    def __new__(metaclass, strName, tupBases, dict):
+        if dict.has_key('__new__'):
+            raise SingletonException, 'Can not override __new__ in a Singleton'
+        return super(MetaSingleton,metaclass).__new__(metaclass, strName, tupBases, dict)
+        
+    def __call__(cls, *lstArgs, **dictArgs):
+        raise SingletonException, 'Singletons may only be instantiated through getInstance()'
+
+class Singleton(object):
+    __metaclass__ = MetaSingleton
+
+    def getInstance(cls, *lstArgs):
+        """
+        Call this to instantiate an instance or retrieve the existing instance.
+        If the singleton requires args to be instantiated, include them the first
+        time you call getInstance.        
+        """
+        if cls._isInstantiated():
+            if len(lstArgs) != 0:
+                raise SingletonException, 'If no supplied args, singleton must already be instantiated, or __init__ must require no args'
+        else:
+            if cls._getConstructionArgCountNotCountingSelf() > 0 and len(lstArgs) <= 0:
+                raise SingletonException, 'If the singleton requires __init__ args, supply them on first instantiation'
+            instance = cls.__new__(cls)
+            instance.__init__(*lstArgs)
+            cls.cInstance = instance
+        return cls.cInstance
+    getInstance = classmethod(getInstance)
+    
+    def _isInstantiated(cls):
+        return hasattr(cls, 'cInstance')
+    _isInstantiated = classmethod(_isInstantiated)  
+
+    def _getConstructionArgCountNotCountingSelf(cls):
+        return cls.__init__.im_func.func_code.co_argcount - 1
+    _getConstructionArgCountNotCountingSelf = classmethod(_getConstructionArgCountNotCountingSelf)