Does that sky have blue color?
Yes, the sky is blue.
    src        edge_attr  dst
0     0   to the left of   16
1     0   to the left of    4
2     0   to the left of   15
3     1           behind    3
4     2   to the left of   12
5     3               on   17
6     3      in front of    1
7     4   to the left of   16
8     4  to the right of   14
9     4   to the left of   15
10    4  to the right of    0
11    5   to the left of   12
12    6   to the left of   10
13    9               of    3
14   10   to the left of   12
15   10  to the right of    6
16   12  to the right of    2
17   12  to the right of    5
18   12  to the right of   10
19   14   to the left of   15
20   14   to the left of    4
21   14   to the left of   16
22   15  to the right of   14
23   15  to the right of    0
24   15  to the right of    4
25   16  to the right of   14
26   16  to the right of    4
27   16  to the right of    0