Do you see balls or fences?
No, there are no fences or balls.
    src        edge_attr  dst
0     3   to the left of    7
1     6  to the right of    9
2     6   to the left of    7
3     7  to the right of    3
4     7  to the right of    9
5     7  to the right of    6
6     7  to the right of   10
7     9               of    3
8     9   to the left of    7
9     9   to the left of    6
10   10   to the left of    7