Which color is the bus?
The bus is black.
    src        edge_attr  dst
0     1               on   11
1     1  to the right of   13
2     1  to the right of    5
3     1  to the right of   12
4     1  to the right of   11
5     2  to the right of   13
6     2  to the right of   14
7     2               of    9
8     2  to the right of    7
9     3  to the right of   11
10    4   to the left of   10
11    4               of   13
12    4   to the left of   11
13    5               on   11
14    5   to the left of    1
15    5   to the left of    6
16    5           behind   13
17    6  to the right of    7
18    6  to the right of    5
19    6  to the right of   12
20    6  to the right of   13
21    7   to the left of   14
22    7  to the right of    9
23    7  to the right of    8
24    7   to the left of    2
25    7   to the left of    6
26    8   to the left of   15
27    8   to the left of    7
28    9   to the left of    7
29    9               on    0
30    9   to the left of   15
31   10  to the right of    4
32   11   to the left of    3
33   11  to the right of    4
34   11   to the left of    1
35   12   to the left of    6
36   12   to the left of    1
37   13               on   11
38   13      in front of    5
39   13   to the left of    2
40   13   to the left of    6
41   13   to the left of    1
42   13           riding   11
43   14  to the right of    7
44   14   to the left of    2
45   15  to the right of    9
46   15  to the right of    8