What kind of vehicle is in front of the wall?
The vehicle is a van.
    src        edge_attr  dst
0     0            below    5
1     0   to the left of    3
2     2           behind    7
3     2            below    3
4     3  to the right of    4
5     3   to the left of   11
6     3  to the right of    0
7     4               on    5
8     4   to the left of    3
9     5       mounted on    9
10    5   to the left of   11
11    5           behind    5
12    5      in front of    5
13    6               on    0
14    6   to the left of    9
15    7      in front of    2
16    7               in    8
17    7  to the right of   10
18    7  to the right of   12
19    7  to the right of    9
20    9   to the left of   10
21    9   to the left of    7
22    9   to the left of   12
23    9  to the right of    6
24    9  to the right of   15
25   10   to the left of    7
26   10  to the right of   15
27   10  to the right of    9
28   11               of    3
29   11  to the right of    3
30   11  to the right of    5
31   12   to the left of   14
32   12  to the right of    9
33   12  to the right of   15
34   12               in    8
35   12   to the left of    7
36   14  to the right of   12
37   15   to the left of   10
38   15   to the left of   12
39   15   to the left of    9