The sky is of what color?
The sky is white.
    src        edge_attr  dst
0     0   to the left of    6
1     1  to the right of    2
2     2   to the left of    1
3     2   to the left of    3
4     2   to the left of    5
5     3               on    4
6     3  to the right of    2
7     4  to the right of   11
8     5  to the right of    2
9     6   to the left of   11
10    6               on   12
11    6  to the right of    9
12    6  to the right of    0
13    8   to the left of   11
14    9   to the left of   11
15    9               on   12
16    9   to the left of    6
17   11  to the right of    8
18   11  to the right of    9
19   11   to the left of    4
20   11  to the right of    6