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