What is on the sign which is on the pole?
The arrow is on the sign.
    src        edge_attr  dst
0     0   to the left of   17
1     0  to the right of    1
2     1   to the left of    0
3     2               on    9
4     4  to the right of   12
5     4   to the left of    5
6     5  to the right of    4
7     5  to the right of   13
8     5  to the right of   10
9     8   to the left of   16
10   10   to the left of    5
11   10  to the right of   12
12   11           behind   17
13   12   to the left of    4
14   12   to the left of   10
15   13   to the left of    5
16   14               on   17
17   14               on   19
18   16  to the right of    8
19   17  to the right of    0
20   17               on   18
21   17      in front of   11
22   20               on   17