Which place is it?
It is a forest.
    src        edge_attr  dst
0     0  to the right of    7
1     0  to the right of    2
2     1   to the left of   11
3     1   to the left of   15
4     1   to the left of    2
..  ...              ...  ...
63   16   to the left of    3
64   17   to the left of    2
65   17   to the left of    7
66   17   to the left of   11
67   17   to the left of   15

[68 rows x 3 columns]