Is this a metallic fence?
No, this is a wooden fence.
    src        edge_attr  dst
0     0   to the left of   11
1     1   to the left of   19
2     1   to the left of   10
3     1   to the left of    4
4     1   to the left of   20
5     2  to the right of    5
6     3   to the left of   10
7     4   to the left of   10
8     4   to the left of   20
9     4  to the right of    1
10    4   to the left of   19
11    5   to the left of    2
12    6  to the right of   14
13    7   to the left of   19
14    7  to the right of    9
15    9               of   15
16    9   to the left of    7
17   10   to the left of   19
18   10   to the left of   20
19   10  to the right of    1
20   10  to the right of    4
21   10  to the right of    3
22   11               of   15
23   11   to the left of   19
24   11   to the left of   20
25   11  to the right of    0
26   12   to the left of   19
27   14  to the right of   17
28   14  to the right of   15
29   14   to the left of    6
30   15   to the left of   14
31   15   to the left of   19
32   15   to the left of   20
33   16   to the left of   19
34   17   to the left of   14
35   19  to the right of   15
36   19  to the right of   10
37   19  to the right of   11
38   19  to the right of   12
39   19  to the right of    4
40   19  to the right of    1
41   19  to the right of   16
42   19  to the right of    7
43   20  to the right of   15
44   20  to the right of    4
45   20  to the right of    1
46   20  to the right of   10
47   20  to the right of   11