Which kind of vehicle is on the road?
The vehicle is a bus.
    src        edge_attr  dst
0     2   to the left of    9
1     2   to the left of   10
2     3  to the right of    7
3     4   to the left of    8
4     4  to the right of    7
5     4               of   10
6     5  to the right of    7
7     7   to the left of    4
8     7   to the left of    3
9     7   to the left of    5
10    7   to the left of   10
11    8  to the right of    4
12    8  to the right of   10
13    9  to the right of    2
14    9   to the left of   10
15   10  to the right of    2
16   10  to the right of    9
17   10               on    0
18   10  to the right of    7
19   10   to the left of    8