3 node [fontsize="13" fontname="Verdana" shape="square"];
4 edge [fontsize="12" fontname="Verdana" color="white" arrowhead="closed" arrowsize="1"];
6 node_service_container [label="service_container (Psr\Container\ContainerInterface, Symfony\Component\DependencyInjection\ContainerInterface)\nSymfony\\Component\\DependencyInjection\\ContainerInterface\n", shape=square, fillcolor="grey", style="filled"];
7 node_foo [label="foo\nFooClass\n", shape=square, fillcolor="grey", style="filled"];
8 node_bar [label="bar\n\n", shape=square, fillcolor="red", style="empty"];
9 node_foo -> node_bar [label="" style="filled"];