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