What vehicle is huge?
The vehicle is a bus.
   src        edge_attr  dst
0    0               on    1
1    0               on    2
2    0   to the left of    1
3    1  to the right of    0
4    1            below    3
5    1  to the right of    2
6    2               on    1
7    2   to the left of    1
8    3            above    4
9    4               on    1