What do the box and the pole have in common?
The color, both the box and the pole are white.
   src        edge_attr  dst
0    0  to the right of    1
1    1   to the left of    0
2    1  to the right of    4
3    2   to the left of    3
4    3  to the right of    2
5    3  to the right of    4
6    4   to the left of    1
7    4   to the left of    3