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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 set (self, id, param, value):
 """ Sets the value of a configuration parameter. """

        assert isinstance(id, basestring)
        assert isinstance(param, basestring)
        assert is_iterable_typed(value, basestring)
        self.params_.setdefault(param, {})[id] = value