Do you see either fences or mailboxes there?
Yes, there is a fence.
    src        edge_attr  dst
0     0  to the right of    6
1     2   to the left of   18
2     2  to the right of    6
3     3   to the left of    7
4     3  to the right of    6
..  ...              ...  ...
84   23  to the right of    9
85   23  to the right of   16
86   25  to the right of    6
87   27   to the left of   28
88   28  to the right of   27

[89 rows x 3 columns]