What kind of animal is the grass behind of?
The grass is behind the zebra.
    src        edge_attr  dst
0     0               in    7
1     1  to the right of   10
2     1  to the right of    3
3     1  to the right of   13
4     2   to the left of    9
5     2   to the left of    6
6     3   to the left of    1
7     3   to the left of    8
8     5  to the right of    8
9     6  to the right of    2
10    8   to the left of    5
11    8  to the right of    3
12    8  to the right of   13
13    8  to the right of   10
14    9  to the right of    2
15   10   to the left of    1
16   10   to the left of    8
17   12           behind   13
18   12           behind    4
19   13   to the left of    8
20   13   to the left of    1