What is on the tree?
The truck is on the tree.
    src        edge_attr  dst
0     0  to the right of    8
1     0  to the right of    2
2     0  to the right of   11
3     0  to the right of    6
4     1  to the right of    5
..  ...              ...  ...
60   14  to the right of   12
61   14  to the right of    9
62   15  to the right of    9
63   15  to the right of   12
64   15   to the left of    8

[65 rows x 3 columns]