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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_nodes(self, new_nodes):
 """Add the given dict of new nodes to the manifest."""

        for unique_id, node in new_nodes.items():
            if unique_id in self.nodes:
                raise_duplicate_resource_name(node, self.nodes[unique_id])
            self.nodes[unique_id] = node