Are there trucks or trains that are not red?
No, there is a truck but it is red.
    src        edge_attr  dst
0     0  to the right of    2
1     1               of   13
2     2   to the left of    0
3     3  to the right of    6
4     4  to the right of   13
5     4               of   12
6     4   to the left of   14
7     4  to the right of    9
8     5               of   12
9     5  to the right of   13
10    5   to the left of   14
11    6   to the left of    3
12    7   to the left of   14
13    8  to the right of   13
14    8               of   12
15    9               of   12
16    9   to the left of   14
17    9   to the left of    4
18   11   to the left of   14
19   11               of   12
20   12   to the left of   14
21   12               on    6
22   12               of    6
23   13   to the left of    4
24   13   to the left of    5
25   13   to the left of    8
26   13   to the left of   14
27   14  to the right of    5
28   14  to the right of    7
29   14  to the right of   13
30   14  to the right of   12
31   14  to the right of   11
32   14  to the right of    9
33   14  to the right of    4