Are there black numbers in the picture?
No, there are numbers but they are blue.
    src        edge_attr  dst
0     0  to the right of   13
1     0   to the left of   14
2     0               of    2
3     1               of    2
4     1   to the left of   15
..  ...              ...  ...
63   15  to the right of   11
64   16            above    8
65   17   to the left of   12
66   17               of    2
67   17  to the right of   13

[68 rows x 3 columns]