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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 restrictCheckers(self, allowedMessages):
 """ Unregister useless checkers to speed up twistedchecker. @param allowedMessages: output messages allowed in twistedchecker """

        uselessCheckers = self.findUselessCheckers(allowedMessages)
        # Unregister these checkers
        for checker in uselessCheckers:
            self.unregisterChecker(checker)