What color is the box on the right of the picture?
The box is gray.
    src        edge_attr  dst
0     0   to the left of    4
1     1  to the right of   15
2     1  to the right of   16
3     1               in    9
4     1  to the right of   14
5     2  to the right of    5
6     2   to the left of    4
7     2       picking up    4
8     2          leaving    9
9     2               at    9
10    3  to the right of    5
11    3  to the right of   10
12    3  to the right of    6
13    4  to the right of    2
14    4  to the right of   12
15    4  to the right of    0
16    5   to the left of    3
17    5   to the left of    2
18    5   to the left of    6
19    5  to the right of    8
20    6   to the left of    3
21    6  to the right of   10
22    6  to the right of    5
23    7  to the right of   16
24    8   to the left of    5
25   10   to the left of    3
26   10   to the left of    6
27   12   to the left of    4
28   13  to the right of   16
29   13  to the right of   14
30   14   to the left of    1
31   14   to the left of   13
32   15   to the left of    1
33   16   to the left of   13
34   16   to the left of    7
35   16   to the left of    1