Who is wearing hats?
The people are wearing hats.
    src        edge_attr  dst
0     1  to the right of   18
1     1  to the right of    6
2     3             near    4
3     4          next to    3
4     4     covered with   10
5     4               on    1
6     4             near    3
7     6           behind   14
8     6          wearing   18
9     6          wearing   13
10    6         carrying   18
11    6   to the left of   14
12    6   to the left of    1
13    7         lying on    1
14    7             near    8
15    8             near    7
16   10       resting on    4
17   10       sitting in    0
18   10             with   20
19   11   to the left of   15
20   13   to the left of   14
21   14  to the right of   17
22   14  to the right of   13
23   14      in front of    6
24   14  to the right of   18
25   14  to the right of    6
26   15             with   11
27   15  to the right of   11
28   17   to the left of   14
29   18   to the left of   14
30   18   to the left of    1