What is the door made of?
The door is made of wood.
   src        edge_attr  dst
0    0   to the left of    1
1    0  to the right of    3
2    1  to the right of    2
3    1  to the right of    3
4    1  to the right of    0
5    2   to the left of    1
6    3   to the left of    1
7    3   to the left of    0