What color are the cans?
The cans are gray.
    src        edge_attr  dst
0     0  to the right of   20
1     0  to the right of   19
2     0  to the right of   14
3     0  to the right of    8
4     0   to the left of   18
..  ...              ...  ...
79   19   to the left of   16
80   19   to the left of   10
81   19   to the left of   15
82   19   to the left of   11
83   20   to the left of    0

[84 rows x 3 columns]