What's on the post?
The sign is on the post.
    src        edge_attr  dst
0     0  to the right of    6
1     0  to the right of    5
2     0  to the right of   13
3     0  to the right of   10
4     0   to the left of   14
..  ...              ...  ...
62   18  to the right of   13
63   18  to the right of    9
64   18  to the right of   10
65   18  to the right of    6
66   18  to the right of   15

[67 rows x 3 columns]