What color is that sky?
The sky is white.
    src        edge_attr  dst
0     0    surrounded by    2
1     0   to the left of    3
2     0               on    3
3     1   to the left of    3
4     2   to the left of    3
5     3  to the right of    4
6     3  to the right of    5
7     3  to the right of    0
8     3  to the right of    2
9     3  to the right of    1
10    4   to the left of    3
11    5   to the left of    3