What is on the bench that is made of cement?
The backpack is on the bench.
    src        edge_attr  dst
0     0  to the right of   12
1     0               on    1
2     0  to the right of   10
3     1   to the left of   14
4     1  to the right of   12
5     1   to the left of   16
6     1  to the right of   10
7     1  to the right of    3
8     1   to the left of   11
9     2   to the left of    6
10    2      in front of    9
11    3   to the left of   12
12    3   to the left of   10
13    3   to the left of    1
14    4  to the right of    7
15    4   to the left of    6
16    5  to the right of    7
17    5   to the left of    6
18    5  to the right of    8
19    6  to the right of    4
20    6  to the right of    5
21    6  to the right of    2
22    6  to the right of    7
23    6  to the right of    8
24    7   to the left of    4
25    7   to the left of    5
26    7   to the left of    6
27    8   to the left of    5
28    8   to the left of    6
29    9           behind    2
30   10               in   15
31   10   to the left of    1
32   10  to the right of    3
33   10   to the left of    0
34   10   to the left of   12
35   11               in   15
36   11               on   16
37   11   to the left of   13
38   11  to the right of    1
39   12   to the left of    0
40   12  to the right of    3
41   12   to the left of    1
42   12  to the right of   10
43   13  to the right of   16
44   13               on   14
45   13  to the right of   11
46   14  to the right of    1
47   16  to the right of    1
48   16   to the left of   13