What is on the shelf?
The flowers are on the shelf.
    src        edge_attr  dst
0     0   to the left of    7
1     0   to the left of    4
2     0  to the right of    9
3     1   to the left of   17
4     2  to the right of    8
..  ...              ...  ...
60   20   to the left of   18
61   20  to the right of   19
62   21   to the left of   14
63   21  to the right of   11
64   21  to the right of    2

[65 rows x 3 columns]