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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 add_rule(self, name, callable_):
 """Makes rule 'name' available to all subsequently loaded Jamfiles. Calling that rule wil relay to 'callable'."""

        assert isinstance(name, basestring)
        assert callable(callable_)
        self.project_rules_.add_rule(name, callable_)