What does the towel which to the left of the surfboard hang on?
The towel hangs on the branch.
    src        edge_attr  dst
0     0   to the left of    4
1     0       hanging on    9
2     0   to the left of   15
3     1        on top of   10
4     2   to the left of   14
5     2  to the right of   15
6     2   to the left of    3
7     2      in front of   11
8     2   to the left of   12
9     3               of   14
10    3  to the right of    2
11    3   to the left of   12
12    3  to the right of   16
13    4  to the right of    0
14    4   to the left of   15
15    6   to the left of   12
16    6               of   14
17    6   to the left of    8
18    7  to the right of   11
19    8  to the right of    6
20    8  to the right of   14
21    8  to the right of   12
22    8  to the right of   11
23    9   to the left of   15
24    9   to the left of   13
25   11           behind    2
26   11   to the left of    7
27   11   to the left of    8
28   11  to the right of   15
29   12  to the right of    3
30   12  to the right of   16
31   12   to the left of    8
32   12  to the right of    2
33   12  to the right of    6
34   12  to the right of   14
35   13  to the right of    9
36   14  to the right of   16
37   14  to the right of    2
38   14   to the left of    8
39   14   to the left of   12
40   14       sitting on    1
41   14       sitting on   10
42   15  to the right of    0
43   15   to the left of    2
44   15   to the left of   11
45   15  to the right of    4
46   15  to the right of    9
47   15         stuck in    1
48   16   to the left of    3
49   16   to the left of   14
50   16   to the left of   12