Returns all data nodes of the dispatcher.

        :return:
            All data nodes of the dispatcher.
        :rtype: dict[str, dict]

def data_nodes(self):
        """
        Returns all data nodes of the dispatcher.

        :return:
            All data nodes of the dispatcher.
        :rtype: dict[str, dict]
        """

        return {k: v for k, v in self.nodes.items() if v['type'] == 'data'}