def METHOD_NAME(graph: DataflowGraph) -> None:
    x: AssignableNodeReference = get_dataflow_node(graph, "x")
    y: AssignableNodeReference = get_dataflow_node(graph, "y")
    x.assign(y, Statement(), graph)
    y.assign(create_instance().reference(), Statement(), graph)
    assert isinstance(y, VariableNodeReference)
    assert len(y.node.instance_assignments) == 1
    y_n: AssignableNodeReference = get_dataflow_node(graph, "y.n")
    y_n.assign(ValueNode(42).reference(), Statement(), graph)
    x_n: AssignableNodeReference = get_dataflow_node(graph, "x.n")
    x_n_nodes: List[AssignableNode] = list(x_n.nodes())
    assert len(x_n_nodes) == 1
    assert x_n_nodes[0] == y.node.instance_assignments[0].rhs.node().get_attribute("n")