How tall is the green grass?
The grass is tall.
    src        edge_attr  dst
0     0   to the left of   11
1     0  to the right of    7
2     2               on    1
3     5   to the left of    8
4     5  to the right of    9
5     6   to the left of    8
6     7   to the left of   11
7     7   to the left of    0
8     7   to the left of   10
9     8  to the right of    9
10    8  to the right of    6
11    8  to the right of    5
12    9   to the left of   11
13    9   to the left of    8
14    9   to the left of    5
15   10  to the right of    7
16   11  to the right of    7
17   11  to the right of    9
18   11  to the right of    0