Is the sky white or blue?
The sky is white.
   src        edge_attr  dst
0    0               on    4
1    0   to the left of    5
2    3   to the left of    5
3    5  to the right of    0
4    5  to the right of    3
5    6   to the left of    9
6    7               on    6
7    9  to the right of    6