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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 perform_authentication(self):
 """ Perform authentication on the incoming request. """


        if not self.authenticators:
            return

        request.user = None
        request.auth = None

        for authenticator in self.authenticators:
            auth_tuple = authenticator.authenticate()

            if auth_tuple:
                request.user = auth_tuple[0]
                request.auth = auth_tuple[1]
                break