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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def addBoth(self, callback, *args, **kw):
 """ Add a single callback as both success and failure callbacks. @return: C{self} @rtype: L{DeferredContext} @raises AlreadyFinished: L{DeferredContext.addActionFinish} has been called. This indicates a programmer error. """

        return self.addCallbacks(callback, callback, args, kw, args, kw)