What is located on top of the sandwich?
The loaf is on top of the sandwich.
    src        edge_attr  dst
0     0           behind   13
1     0  to the right of    2
2     0        on top of   12
3     0  to the right of    3
4     1             with    9
5     1        on top of    6
6     1   to the left of    7
7     1   to the left of   10
8     2           inside    3
9     2   to the left of    0
10    2   to the left of   12
11    3   to the left of   13
12    3   to the left of    0
13    3        on top of    4
14    3   to the left of   12
15    5        on top of    6
16    7  to the right of   11
17    7       leaning on    6
18    7          holding   10
19    7  to the right of    1
20    8  to the right of   14
21    8           inside    1
22    8        on top of   11
23    9        on top of    1
24   10        on top of    7
25   10               on    7
26   10  to the right of   11
27   10  to the right of    1
28   11  to the right of   14
29   11   to the left of    7
30   11   to the left of   10
31   12  to the right of    2
32   12  to the right of    3
33   13  to the right of    3
34   13        on top of    4
35   13      in front of    0
36   14        on top of    6
37   14   to the left of    8
38   14   to the left of   11