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