What vehicle is in front of the tree?
The vehicle is a train.
    src        edge_attr  dst
0     0        pulled by   11
1     0  to the right of   11
2     0   to the left of    1
3     1  to the right of   11
4     1        pulled by   11
5     1  to the right of    0
6     3  to the right of    6
7     3            above   11
8     3  to the right of   12
9     4               of   13
10    5           behind   11
11    5   to the left of   12
12    5   to the left of   11
13    6   to the left of   14
14    6   to the left of    3
15    6            above   11
16    7  to the right of   11
17    7               on   13
18   11      in front of    5
19   11          pulling    1
20   11          pulling    0
21   11   to the left of    7
22   11            below    6
23   11            below   12
24   11            below    3
25   11   to the left of    1
26   11  to the right of    5
27   11   to the left of    0
28   12   to the left of    3
29   12  to the right of    5
30   12            above   11
31   14  to the right of    6