Which kind of sign isn't white?
The sign is a stop sign.
    src        edge_attr  dst
0     0   to the left of    7
1     0   to the left of    2
2     0   to the left of   11
3     0   to the left of    8
4     1               on   10
5     1   to the left of    8
6     2  to the right of    4
7     2  to the right of    0
8     2   to the left of    8
9     3   to the left of    8
10    3  to the right of    5
11    4               on    7
12    4   to the left of    2
13    5   to the left of    3
14    6   to the left of    8
15    7  to the right of    0
16    7   to the left of    8
17    8  to the right of    7
18    8  to the right of   10
19    8  to the right of   11
20    8  to the right of    0
21    8  to the right of    1
22    8  to the right of    2
23    8  to the right of    6
24    8  to the right of    3
25   10   to the left of    8
26   11  to the right of    0
27   11   to the left of    8