What are the vehicles that are green called?
The vehicles are buses.
    src        edge_attr  dst
0     0      in front of   14
1     0      in front of    6
2     0  to the right of    4
3     0   to the left of    9
4     0   to the left of   16
5     1           behind   14
6     1  to the right of   11
7     1   to the left of   10
8     2  to the right of   14
9     2  to the right of    6
10    2  to the right of    5
11    3   to the left of    5
12    3   to the left of   14
13    3  to the right of    8
14    3   to the left of    9
15    3  to the right of    7
16    4           inside    3
17    4  to the right of    7
18    4   to the left of    0
19    5  to the right of    3
20    5   to the left of    2
21    6   to the left of    2
22    6  to the right of    8
23    6  to the right of    7
24    6           behind    0
25    7   to the left of    4
26    7   to the left of    6
27    7   to the left of    3
28    7               on    8
29    8   to the left of    6
30    8   to the left of    3
31    9  to the right of    3
32    9  to the right of    0
33   10  to the right of    1
34   11   to the left of    1
35   14  to the right of   15
36   14      in front of    1
37   14  to the right of    3
38   14           behind    0
39   14   to the left of    2
40   15   to the left of   14
41   16  to the right of    0