What is in the pocket?
The envelope is in the pocket.
    src        edge_attr  dst
0     0   to the left of   19
1     0   to the left of   18
2     0   to the left of    7
3     0   to the left of   16
4     0   to the left of    8
..  ...              ...  ...
90   24               in   10
91   24   to the left of   21
92   24   to the left of   23
93   25  to the right of    5
94   25   to the left of    3

[95 rows x 3 columns]