What kind of vehicle is to the left of the van?
The vehicles are cars.
    src        edge_attr  dst
0     0               by    4
1     1  to the right of    7
2     1  to the right of    8
3     1  to the right of    3
4     1   to the left of   18
5     1   to the left of   15
6     2  to the right of    9
7     3   to the left of    5
8     3   to the left of    1
9     3   to the left of    6
10    3   to the left of   10
11    5  to the right of    8
12    5  to the right of    3
13    6  to the right of    3
14    6  to the right of    8
15    6   to the left of   20
16    6   to the left of   19
17    7   to the left of    1
18    8   to the left of    1
19    8   to the left of    5
20    8   to the left of   10
21    8   to the left of    6
22    8               on    4
23    9   to the left of   16
24    9   to the left of   17
25    9   to the left of    2
26    9   to the left of   11
27   10  to the right of    3
28   10  to the right of    8
29   10   to the left of   20
30   10   to the left of   19
31   11  to the right of   17
32   11  to the right of    9
33   15  to the right of   20
34   15  to the right of    1
35   15  to the right of   19
36   16  to the right of    9
37   17   to the left of   11
38   17  to the right of    9
39   18  to the right of    1
40   18  to the right of   20
41   18  to the right of   19
42   19            using   11
43   19  to the right of    6
44   19   to the left of   18
45   19   to the left of   15
46   19  to the right of   10
47   19          holding   11
48   19          wearing    2
49   20  to the right of   10
50   20   to the left of   15
51   20   to the left of   18
52   20  to the right of    6