What's the fork made of?
The fork is made of metal.
   src        edge_attr  dst
0    0               on    3
1    0               on    5
2    0               on    6
3    1  to the right of    2
4    2   to the left of    4
5    2   to the left of    1
6    4  to the right of    2
7    4               on    1