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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 rule_function_not_found(self, fun=None):
 """ any function that does not exist will be added as a dummy function that will gather inputs for easing into the possible future implementation """

        sfun = str(fun)
        self.cry('rule_function_not_found:' + sfun)

        def not_found(*a, **k):
            return(sfun + ':rule_function_not_found', k.keys())
        return not_found