What is on the pole made of metal?
The stop sign is on the pole.
    src        edge_attr  dst
0     0   to the left of    6
1     0   to the left of   15
2     0  to the right of   11
3     1  to the right of   13
4     1             near   11
5     1   to the left of   14
6     1   to the left of   15
7     1   to the left of    8
8     1   to the left of   18
9     1   to the left of    3
10    1        on top of    0
11    1               on    0
12    2            above    4
13    2   to the left of   19
14    2  to the right of    5
15    2   to the left of    3
16    3            above   17
17    3            above   14
18    3  to the right of    2
19    3  to the right of   13
20    3  to the right of    5
21    3  to the right of    4
22    3  to the right of    1
23    4            below    2
24    4   to the left of    3
25    5   to the left of    3
26    5   to the left of    7
27    5   to the left of    2
28    6             near   17
29    6  to the right of    0
30    7  to the right of    5
31    8  to the right of    1
32    9  to the right of   16
33    9  to the right of   15
34   11             near    1
35   11   to the left of   15
36   11   to the left of    0
37   12   to the left of   17
38   12  to the right of   15
39   13   to the left of   18
40   13   to the left of    3
41   13   to the left of    1
42   14            below    3
43   14  to the right of    1
44   15   to the left of   16
45   15   to the left of    9
46   15  to the right of    0
47   15  to the right of    1
48   15   to the left of   12
49   15  to the right of   11
50   16  to the right of   15
51   16   to the left of    9
52   17             near    6
53   17  to the right of   12
54   17            under    3
55   17            below    3
56   18  to the right of    1
57   18  to the right of   13
58   19  to the right of    2