Is the bus different in color than the plane?
No, both the bus and the plane are white.
    src        edge_attr  dst
0     0      in front of    1
1     1               on   18
2     1   to the left of    2
3     1   to the left of   11
4     1   to the left of    4
5     1           behind    0
6     2  to the right of    4
7     2  to the right of    1
8     2  to the right of   11
9     2             near   12
10    3  to the right of    9
11    3  to the right of   15
12    3  to the right of   16
13    4  to the right of    1
14    4   to the left of    2
15    5           behind   18
16    6   to the left of   12
17    9   to the left of   16
18    9  to the right of   15
19    9   to the left of    3
20   11  to the right of    1
21   11          exiting    1
22   11   to the left of    2
23   12             near    2
24   12  to the right of    6
25   12          exiting    1
26   15   to the left of    9
27   15   to the left of    3
28   15   to the left of   16
29   16  to the right of    9
30   16   to the left of    3
31   16  to the right of   15