What is on the wall?
The light switch is on the wall.
    src        edge_attr  dst
0     0   to the left of    1
1     0   to the left of   19
2     0  to the right of   11
3     0  to the right of   17
4     0   to the left of   10
..  ...              ...  ...
81   18   to the left of    4
82   19  to the right of    0
83   19   to the left of    8
84   19  to the right of    3
85   19   to the left of   10

[86 rows x 3 columns]