Are there grinders or nests?
No, there are no nests or grinders.
   src        edge_attr  dst
0    1   to the left of    4
1    4  to the right of    1
2    4  to the right of    8
3    6   to the left of    7
4    7  to the right of    6
5    8               on    4
6    8   to the left of    4
7    9            above    8