Is the toilet paper on the right or on the left?
The toilet paper is on the left of the image.
   src        edge_attr  dst
0    1   to the left of    5
1    3  to the right of    7
2    5  to the right of    6
3    5  to the right of    1
4    6   to the left of    5
5    6               on    1
6    7   to the left of    3