What type of sign is the same color as the wall?
The stop sign is the same color as the wall.
    src        edge_attr  dst
0     0   to the left of    5
1     1   to the left of    2
2     1  to the right of    5
3     2  to the right of    5
4     2  to the right of    1
5     2  to the right of    6
6     3               on    1
7     5  to the right of    0
8     5   to the left of    2
9     5   to the left of    1
10    6   to the left of    2