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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_node(self, host, port, server_type=None):
 """ Update data for a node. """

        node_name = "{0}:{1}".format(host, port)
        node = {
            'host': host,
            'port': port,
            'name': node_name,
            'server_type': server_type
        }
        self.nodes[node_name] = node
        return node