Are there both bridges and fences in the picture?
Yes, there are both a bridge and a fence.
    src        edge_attr  dst
0     0   to the left of   15
1     0  to the right of   17
2     0               of    7
3     1   to the left of   15
4     2   to the left of    8
5     2           around   10
6     2  to the right of   10
7     2   to the left of    6
8     2   to the left of   15
9     3   to the left of   15
10    4  to the right of    5
11    4   on the side of    8
12    5  to the right of   13
13    5  to the right of   11
14    5   to the left of    4
15    6  to the right of    2
16    6  to the right of    7
17    6  to the right of   10
18    7   to the left of    6
19    7   to the left of   18
20    7   to the left of   16
21    7  to the right of   17
22    7   to the left of    8
23    7  to the right of   11
24    8  to the right of   10
25    8  to the right of    7
26    8   to the left of   12
27    8  to the right of    2
28    8   to the left of    9
29    9  to the right of    8
30   10   to the left of   15
31   10   to the left of    6
32   10   to the left of    8
33   10   to the left of    2
34   10  to the right of   11
35   11   to the left of    5
36   11   to the left of   13
37   11   to the left of   10
38   11   to the left of    7
39   12  to the right of   18
40   12  to the right of    8
41   13  to the right of   11
42   13   to the left of    5
43   14   to the left of   15
44   15  to the right of    0
45   15  to the right of    1
46   15  to the right of    2
47   15  to the right of   10
48   15  to the right of   14
49   15  to the right of    3
50   16  to the right of    7
51   17   to the left of    0
52   17   to the left of    7
53   18   to the left of   12
54   18               of    8
55   18  to the right of    7