Do you see bridges there?
No, there are no bridges.
    src        edge_attr  dst
0     0  to the right of    8
1     0  to the right of   13
2     0   to the left of   12
3     0  to the right of   10
4     1  to the right of    8
5     1   to the left of   12
6     2   to the left of    9
7     5   to the left of   12
8     5  to the right of    8
9     5  to the right of   11
10    7  to the right of   11
11    8               on   14
12    8   to the left of    1
13    8  to the right of   13
14    8   to the left of    0
15    8  to the right of   10
16    8   to the left of    5
17    9  to the right of    2
18    9  to the right of   11
19   10   to the left of    0
20   10   to the left of    8
21   10   to the left of   13
22   11   to the left of   12
23   11   to the left of    5
24   11            using    0
25   11   to the left of    9
26   11   to the left of    7
27   12  to the right of    1
28   12  to the right of    5
29   12  to the right of    0
30   12  to the right of   11
31   13  to the right of   10
32   13   to the left of    8
33   13   to the left of    0