What is the sink made of?
The sink is made of glass.
    src        edge_attr  dst
0     0  to the right of    3
1     0  to the right of    7
2     3               on    7
3     3   to the left of    0
4     4  to the right of    8
5     7   to the left of    0
6     8   to the left of    4
7     9   to the left of   10
8     9               on    2
9    10  to the right of    9
10   10               on    2