What is the train in front of?
The train is in front of the crane.
    src        edge_attr  dst
0     0  to the right of   13
1     0  to the right of   12
2     1   to the left of   13
3     2           beside   14
4     2   to the left of    4
..  ...              ...  ...
72   18   to the left of   11
73   18   to the left of    2
74   19               on   18
75   19  to the right of    3
76   19  to the right of    5

[77 rows x 3 columns]