What type of animal is this, a cow or a pig?
That is a cow.
   src        edge_attr  dst
0    1   to the left of    3
1    2   to the left of    5
2    2   to the left of    3
3    3  to the right of    1
4    3  to the right of    2
5    3  to the right of    7
6    3  to the right of    6
7    5  to the right of    2
8    6   to the left of    3
9    7   to the left of    3