What is located on top of the building that is on top of the building?
The ornament is on top of the tower.
   src        edge_attr  dst
0    0               on    2
1    0  on the front of    2
2    1           behind   11
3    2        on top of   11
4    3               on    0
5    6               on   11
6    7               on    2
7    9        on top of    2