What is the sign on?
The sign is on the post.
    src        edge_attr  dst
0     0   to the left of   10
1     0   to the left of    9
2     0   to the left of   18
3     0   to the left of   11
4     1   to the left of   14
..  ...              ...  ...
74   21  to the right of    3
75   21               on   11
76   21  to the right of    7
77   21  to the right of   15
78   21   to the left of   19

[79 rows x 3 columns]