What vehicle is it?
The vehicle is a train.
    src        edge_attr  dst
0     0  to the right of    4
1     0   to the left of    6
2     1               of    6
3     1  to the right of    7
4     2  to the right of    3
5     2  to the right of    6
6     3   to the left of    2
7     4   to the left of    6
8     4   to the left of   14
9     4   to the left of    0
10    4   to the left of    8
11    6               by   11
12    6  to the right of   10
13    6  to the right of    0
14    6  to the right of    4
15    6   to the left of    2
16    6  to the right of    7
17    6  to the right of   12
18    6  to the right of    8
19    7   to the left of    6
20    7   to the left of    1
21    7               by    6
22    8   to the left of    6
23    8  to the right of   12
24    8  to the right of    4
25   10   to the left of    6
26   12   to the left of    8
27   12   to the left of    6
28   14  to the right of    4