What is the vehicle that is to the left of the van?
The vehicle is a car.
    src        edge_attr  dst
0     1          wearing    2
1     1  to the right of    4
2     2   to the left of    6
3     4   to the left of    6
4     4   to the left of    5
5     4   to the left of    1
6     5  to the right of    4
7     5   to the left of    6
8     6  to the right of    4
9     6   to the left of   12
10    6  to the right of    5
11    6  to the right of    2
12    8   to the left of    9
13    9  to the right of    8
14   11               on    1
15   12  to the right of    6