What vehicles are to the left of the bus?
The vehicles are cars.
    src        edge_attr  dst
0     0  to the right of   13
1     0   to the left of   10
2     3   to the left of   11
3     3   to the left of    7
4     3  to the right of    6
5     3  to the right of    5
6     5               on   10
7     5   to the left of    7
8     5   to the left of    3
9     5   to the left of   11
10    6   to the left of    7
11    6   to the left of    3
12    7               on   10
13    7               on   13
14    7  to the right of   13
15    7  to the right of    3
16    7  to the right of    6
17    7  to the right of    5
18    7   to the left of   10
19    7   to the left of    8
20    8  to the right of    7
21    9               in    4
22   10  to the right of    0
23   10  to the right of    7
24   11  to the right of    3
25   11  to the right of    5
26   11  to the right of   13
27   13   to the left of    0
28   13   to the left of   11
29   13   to the left of    7