What is the fence in front of?
The fence is in front of the tree.
    src        edge_attr  dst
0     0  to the right of    7
1     0  to the right of    4
2     1   to the left of    8
3     1   to the left of   13
4     1   to the left of   12
5     2  to the right of    7
6     2  to the right of    4
7     2  to the right of    5
8     3   to the left of    9
9     3   to the left of    8
10    3   to the left of   12
11    3  to the right of   10
12    4   to the left of   13
13    4           behind    6
14    4   to the left of    2
15    4   to the left of    8
16    4   to the left of    9
17    4   to the left of   11
18    4   to the left of   12
19    4   to the left of    0
20    5   to the left of    7
21    5   to the left of    2
22    5   to the left of    8
23    6      in front of    4
24    7   to the left of    8
25    7   to the left of    2
26    7   to the left of    0
27    7  to the right of    5
28    8  to the right of    5
29    8  to the right of    4
30    8  to the right of    7
31    8  to the right of    1
32    8  to the right of    3
33    9  to the right of    3
34    9  to the right of    4
35    9   to the left of   12
36   10   to the left of    3
37   10   to the left of   11
38   11  to the right of    4
39   11  to the right of   10
40   12  to the right of    3
41   12  to the right of    4
42   12  to the right of    1
43   12  to the right of   13
44   12  to the right of    9
45   13  to the right of    1
46   13  to the right of    4
47   13   to the left of   12