What is the train on?
The train is on the platform.
    src        edge_attr  dst
0     0  to the right of   13
1     0   to the left of   12
2     1  to the right of    9
3     1               at    6
4     1  to the right of   13
5     1               of    7
6     2  to the right of   12
7     2  to the right of    7
8     3   to the left of    5
9     3               in    2
10    3  to the right of    7
11    4  to the right of   15
12    4  to the right of    7
13    5  to the right of   12
14    5  to the right of    7
15    5               in    2
16    5  to the right of    3
17    6               of    7
18    7  to the right of   11
19    7   to the left of    2
20    7   to the left of    3
21    7   to the left of   14
22    7   to the left of    5
23    7   to the left of    4
24    7   to the left of    8
25    7   to the left of   10
26    7               at    6
27    7               on    1
28    7   to the left of   12
29    8               on    1
30    8  to the right of    7
31    8               of    6
32    9               on    7
33    9   to the left of    1
34   10               on    1
35   10  to the right of    7
36   11   to the left of   13
37   11   to the left of    7
38   12  to the right of    0
39   12  to the right of    7
40   12   to the left of    5
41   12   to the left of    2
42   13               of    7
43   13  to the right of   11
44   13   to the left of    0
45   13   to the left of    1
46   14               in    6
47   14  to the right of   15
48   14  to the right of    7
49   15               at    6
50   15   to the left of    4
51   15   to the left of   14