What is the vehicle that the man is in front of?
The vehicle is a truck.
    src        edge_attr  dst
0     0      in front of    8
1     0  to the right of    3
2     0           behind   12
3     2           behind    7
4     2   to the left of    8
5     2  to the right of   19
6     3  to the right of    7
7     3   to the left of    0
8     3  to the right of   19
9     3           behind   12
10    3   to the left of    8
11    3  to the right of   13
12    5           behind   12
13    5             near   12
14    5  to the right of   15
15    6  to the right of   12
16    6               of   16
17    7          wearing   13
18    7      in front of    2
19    7               by    3
20    7   to the left of    3
21    7           behind   12
22    7       walking by    3
23    7  to the right of   19
24    8  to the right of    2
25    8           behind    0
26    8  to the right of    3
27    9  to the right of   16
28    9  to the right of   17
29   12          wearing   11
30   12      in front of    5
31   12      in front of    3
32   12          wearing   14
33   12             near    5
34   12      in front of    0
35   12      in front of    7
36   12      in front of   17
37   12       sitting on   16
38   12          wearing    4
39   12          wearing   18
40   12   to the left of    6
41   13   to the left of    3
42   13  to the right of   19
43   14  to the right of   18
44   15   to the left of    5
45   16  to the right of   18
46   16   to the left of    9
47   17   to the left of    9
48   17           behind   12
49   18   to the left of   16
50   18   to the left of   14
51   19   to the left of    2
52   19   to the left of    3
53   19   to the left of   13
54   19   to the left of    7