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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_node(self, node):
 """ Add a node to this network, let the node know which network it's on. """

        if _debug: Network._debug("add_node %r", node)

        self.nodes.append(node)
        node.lan = self

        # update the node name
        if not node.name:
            node.name = '%s:%s' % (self.name, node.address)