Are there any knives that are not yellow?
Yes, there is a silver knife.
    src        edge_attr  dst
0     0  to the right of    9
1     1               on   11
2     2               on   11
3     2  to the right of    8
4     3  to the right of   14
5     3   to the left of   10
6     4           beside   13
7     4  to the right of    7
8     4  to the right of    6
9     4  to the right of   13
10    6   to the left of    4
11    7   to the left of    4
12    7  to the right of    8
13    8   to the left of    7
14    8   to the left of    2
15    8   to the left of   11
16    9   to the left of    0
17   10  to the right of    3
18   10  to the right of   14
19   11  to the right of    8
20   13       sitting at    5
21   13   to the left of    4
22   13          wearing    6
23   14   to the left of    3
24   14   to the left of   10