Do you see clocks or flags there?
Yes, there is a flag.
    src        edge_attr  dst
0     0           behind   11
1     1   to the left of   13
2     1  to the right of   11
3     1  to the right of   15
4     1  to the right of    9
5     3   to the left of   11
6     3   to the left of    7
7     4   to the left of   13
8     4               on    1
9     4  to the right of   15
10    4  to the right of   11
11    5  to the right of   13
12    6   to the left of   10
13    7  to the right of    3
14    7  to the right of   12
15    9   to the left of   13
16    9   to the left of    1
17   10  to the right of    6
18   11   to the left of    4
19   11   to the left of    1
20   11      in front of    0
21   11               in    2
22   11  to the right of    3
23   11  to the right of   12
24   12   to the left of   11
25   12   to the left of    7
26   13  to the right of    9
27   13  to the right of   15
28   13  to the right of    1
29   13  to the right of    4
30   13   to the left of    5
31   15   to the left of    1
32   15   to the left of    4
33   15   to the left of   13