What's the train in front of?
The train is in front of the tree.
     src        edge_attr  dst
0      0               on   13
1      0   to the left of    4
2      0   hanging out of   13
3      0   to the left of   11
4      0  to the right of    6
..   ...              ...  ...
113   24               at   20
114   24  to the right of   22
115   24  to the right of   23
116   24   to the left of    1
117   24          next to   13

[118 rows x 3 columns]