Is it the beach or the desert?
It is the beach.
    src        edge_attr  dst
0     0   to the left of   15
1     0   to the left of   11
2     0  to the right of    1
3     1   to the left of    0
4     1               on   17
5     1   to the left of   15
6     2   to the left of   10
7     2  to the right of   13
8     2  to the right of   14
9     2  to the right of    4
10    2  to the right of   15
11    3   to the left of   16
12    4   to the left of   15
13    4   to the left of   11
14    4   to the left of    2
15    7               on   17
16    7               on    3
17    7   to the left of   15
18   10  to the right of    2
19   10               of   15
20   10  to the right of   15
21   11  to the right of   15
22   11  to the right of    4
23   11  to the right of    0
24   12   to the left of   15
25   13               of   15
26   13   to the left of    2
27   14   to the left of    2
28   15   to the left of   10
29   15  to the right of    7
30   15   to the left of    2
31   15  to the right of   12
32   15  to the right of    0
33   15  to the right of    1
34   15   to the left of   11
35   15  to the right of    4
36   15               on   17
37   16  to the right of    3