What device is on the chair?
The device is a controller.
    src        edge_attr  dst
0     1   to the left of    3
1     2               on    0
2     2   to the left of   11
3     3  to the right of    9
4     3  to the right of    1
5     3               on    4
6     4  to the right of    9
7     5               on    0
8     7   to the left of   11
9     9   to the left of    4
10    9   to the left of    3
11   11  to the right of    2
12   11  to the right of    7