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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 node_iterator(self):
 """Provides an iterator over the nodes. """

        return iter(self._node_attributes)

	def has_hypernode(self, hypernode):
        """Determines if a specific hypernode is present in the hypergraph.

        :param node: reference to hypernode whose presence is being checked.
        :returns: bool -- true iff the node exists in the hypergraph.

        """
        return hypernode in self._hypernode_attributes