What are the characters on?
The characters are on the sign.
    src        edge_attr  dst
0     0   to the left of    6
1     0   to the left of    2
2     0   to the left of    7
3     1   to the left of    6
4     1             near    9
5     2               on    7
6     2  to the right of    3
7     2  to the right of    0
8     2  to the right of    4
9     3   to the left of    7
10    3            above    9
11    3   to the left of    2
12    4   to the left of    2
13    4   to the left of    7
14    5   to the left of    6
15    6  to the right of    8
16    6  to the right of    0
17    6  to the right of    1
18    6  to the right of    5
19    7  to the right of    0
20    7  to the right of    3
21    7  to the right of    4
22    8   to the left of    6
23    9               at    0
24    9             near    1
25    9            below    3