Do you see a door there that is made of metal?
Yes, there is a door that is made of metal.
   src        edge_attr  dst
0    0   to the left of    5
1    0   to the left of    4
2    1   to the left of    4
3    1  to the right of    6
4    3   to the left of    4
5    4  to the right of    3
6    4  to the right of    1
7    4  to the right of    0
8    5  to the right of    0
9    6   to the left of    1