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