What type of vehicle is made of the same material as the bucket to the right of the boats?
The trailer is made of the same material as the bucket.
    src        edge_attr  dst
0     0   to the left of   13
1     0   to the left of   16
2     0  to the right of    7
3     0   to the left of    2
4     0               on   18
5     1   to the left of   17
6     2   to the left of   13
7     2  to the right of    0
8     2  to the right of    7
9     2               on   18
10    4   to the left of   14
11    5  to the right of   18
12    6               on    5
13    6  to the right of   18
14    7   to the left of   16
15    7   to the left of    2
16    7               on   18
17    7   to the left of    0
18    8   to the left of   20
19   10  to the right of   14
20   13  to the right of    0
21   13  to the right of    2
22   13  to the right of   16
23   14  to the right of    4
24   14   to the left of   10
25   15   to the left of   17
26   16  to the right of    0
27   16  to the right of    7
28   16               on   18
29   16   to the left of   13
30   17  to the right of   15
31   17  to the right of    1
32   18   to the left of    6
33   18   to the left of    5
34   18             near   20
35   20               by   18
36   20  to the right of    8
37   20             near   18