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