What is covered by the sky?
The mountains are covered by the sky.
     src        edge_attr  dst
0      0  to the right of   16
1      0  to the right of   23
2      0  to the right of    5
3      0   to the left of    9
4      0   to the left of   11
..   ...              ...  ...
104   26   to the left of   23
105   27  to the right of    2
106   27   to the left of   23
107   27  to the right of    6
108   27  to the right of   20

[109 rows x 3 columns]