Is there either a clock or a traffic light?
No, there are no traffic lights or clocks.
   src        edge_attr  dst
0    0  to the right of    4
1    1            below    6
2    2             near    3
3    3          next to    2
4    4   to the left of    0
5    4               in    5
6    5            below    6
7    6               by    7