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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 new_empty(self, name):
 """Make a new rule with no actions or anything, and return it."""

        if name in self:
            raise KeyError("Already have rule {}".format(name))
        new = Rule(self.engine, name)
        self._cache[name] = new
        self.send(self, rule=new, active=True)
        return new