Which side is the box on?
The box is on the right of the image.
   src        edge_attr  dst
0    1  to the right of    8
1    1  to the right of    7
2    2  to the right of    8
3    3               on    6
4    4  to the right of    8
5    7   to the left of    1
6    8   to the left of    1
7    8   to the left of    2
8    8   to the left of    4