On which side is the tower?
The tower is on the right of the image.
   src        edge_attr  dst
0    1   to the left of    7
1    1  to the right of    5
2    2               on    7
3    5  to the right of   11
4    5   to the left of    1
5    7  to the right of    1
6   11   to the left of    5