What is on the dessert to the right of the cream?
The chocolate is on the cake.
   src        edge_attr  dst
0    0               on    2
1    0   to the left of    1
2    1  to the right of    2
3    1  to the right of    0
4    2   to the left of    4
5    2   to the left of    1
6    2  to the right of    3
7    3   to the left of    2
8    4  to the right of    2
9    6               on    5