What is the color of the small train?
The train is blue.
    src        edge_attr  dst
0     0   to the left of    1
1     1  to the right of    7
2     1  to the right of    0
3     1               by    2
4     1  to the right of    2
5     2  to the right of    9
6     2   to the left of    1
7     2      in front of   10
8     3  to the right of    9
9     3   to the left of   11
10    3   to the left of   10
11    5  to the right of    8
12    5   to the left of    7
13    7   to the left of    1
14    7  to the right of    5
15    8   to the left of    5
16    9   to the left of    2
17    9   to the left of    3
18    9   to the left of   11
19    9   to the left of   10
20   10  to the right of    9
21   10  to the right of    3
22   10           behind    2
23   11  to the right of    9
24   11  to the right of    3