Which material is the mustard made of?
The mustard is made of leather.
    src        edge_attr  dst
0     0  to the right of   16
1     1  to the right of   14
2     2   to the left of   10
3     5   to the left of   14
4     6  to the right of    7
5     7   to the left of    6
6    10  to the right of    2
7    14  to the right of   16
8    14  to the right of    5
9    14   to the left of    1
10   16   to the left of    0
11   16   to the left of   14