What is the vehicle that is on the road?
The vehicle is a bus.
    src        edge_attr  dst
0     0   to the left of    1
1     1   to the left of   10
2     1  to the right of    3
3     1   to the left of   20
4     1   to the left of   14
..  ...              ...  ...
68   21  to the right of    9
69   21  to the right of    2
70   21  to the right of    4
71   21  to the right of   18
72   21  to the right of   16

[73 rows x 3 columns]