What is the train on?
The train is on the tracks.
    src        edge_attr  dst
0     0   to the left of    4
1     0   to the left of    1
2     0   to the left of   13
3     1   to the left of    5
4     1  to the right of    0
..  ...              ...  ...
63   20   to the left of   15
64   21   to the left of   18
65   21   to the left of   15
66   22   to the left of   11
67   22   to the left of   18

[68 rows x 3 columns]