What is in front of the trees?
The train is in front of the trees.
     src        edge_attr  dst
0      0      in front of    5
1      0   to the left of    3
2      0   to the left of   15
3      0   to the left of   20
4      0   to the left of   11
..   ...              ...  ...
96    20  to the right of    9
97    20  to the right of    8
98    20  to the right of    6
99    20  to the right of    0
100   20   to the left of    3

[101 rows x 3 columns]