What is the name of the vehicle to the right of the backpack that the man is holding?
The vehicle is a bus.
    src        edge_attr  dst
0     0  to the right of    4
1     0  to the right of    3
2     0  to the right of   10
3     1   to the left of    5
4     1   to the left of    2
5     1   to the left of    9
6     1          holding   10
7     1   to the left of    7
8     2  to the right of    8
9     2   to the left of   11
10    2          holding   10
11    2  to the right of    1
12    2  to the right of    5
13    3          holding    4
14    3   to the left of    0
15    4   to the left of    0
16    4   to the left of    8
17    5  to the right of    1
18    5   to the left of    2
19    5   to the left of    9
20    5   to the left of   11
21    6   to the left of   11
22    6  to the right of   10
23    7        on top of    0
24    7  to the right of    1
25    8   to the left of   11
26    8  to the right of    4
27    8   to the left of    2
28    9  to the right of    5
29    9  to the right of    1
30   10   to the left of    6
31   10   to the left of    0
32   11  to the right of    8
33   11  to the right of    2
34   11  to the right of    5
35   11  to the right of    6
36   12          holding   11