What is in front of the sky?
The leaves are in front of the sky.
    src        edge_attr  dst
0     0  to the right of    3
1     1  to the right of   12
2     1  to the right of    2
3     1  to the right of   13
4     1  to the right of   10
5     1  to the right of   15
6     2  to the right of   12
7     2  to the right of   14
8     2   to the left of    6
9     2   to the left of    1
10    2  to the right of   11
11    3   to the left of    0
12    3   to the left of    4
13    4  to the right of    3
14    6  to the right of   12
15    6  to the right of    2
16    6  to the right of   10
17    6  to the right of   13
18    7           behind   13
19    8  to the right of   13
20   10   to the left of    6
21   10   to the left of    1
22   10  to the right of   14
23   10      in front of   13
24   10  to the right of   12
25   10  to the right of   11
26   10               on    9
27   11   to the left of    2
28   11   to the left of   10
29   11   to the left of   12
30   12  to the right of   14
31   12   to the left of    2
32   12   to the left of    1
33   12   to the left of   10
34   12   to the left of    6
35   12  to the right of   11
36   13      in front of    7
37   13           behind   10
38   13   to the left of   15
39   13   to the left of    6
40   13   to the left of    1
41   13   to the left of    8
42   13               of   11
43   14   to the left of    2
44   14   to the left of   12
45   14   to the left of   10
46   15   to the left of    1
47   15  to the right of   13