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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 after(func):
 """ Run a function after the handler is invoked, is passed the response and must return an response too. Usage:: {'body': '', 'Headers': {'X-Clacks-Overhead': 'GNU Terry Pratchett'}} """

    class AfterDecorator(LambdaDecorator):
        def after(self, retval):
            return func(retval)

    return AfterDecorator