Are there either any fences or fire hydrants in the scene?
Yes, there is a fence.
    src        edge_attr  dst
0     1  to the right of    3
1     2   to the left of    8
2     3               on    3
3     3   to the left of   14
4     3   to the left of    1
5     3   to the left of    7
6     4  to the right of   10
7     4  to the right of    5
8     5   to the left of    4
9     7  to the right of    3
10    8  to the right of   14
11    8   to the left of    9
12    8  to the right of    2
13    8   to the left of   13
14    8   to the left of   12
15    9  to the right of    8
16   10   to the left of    4
17   11               of    6
18   12  to the right of    8
19   13  to the right of    8
20   14   to the left of    8
21   14  to the right of    3