Do you see any tie there that is not white?
No, there is a tie but it is white.
    src        edge_attr  dst
0     0  to the right of    4
1     2   to the left of    5
2     2  to the right of   11
3     3  to the right of    4
4     4   to the left of    3
..  ...              ...  ...
63   21  to the right of    5
64   21   to the left of   13
65   21  to the right of   20
66   21   to the left of   10
67   21   to the left of   12

[68 rows x 3 columns]