What is the briefcase on?
The brief case is on the bike.
    src        edge_attr  dst
0     0   to the left of    7
1     0   to the left of    3
2     0      hanging off   17
3     1               on   17
4     1   to the left of    2
5     1  to the right of    8
6     2  to the right of    1
7     2  to the right of   17
8     2  to the right of    3
9     3   to the left of    7
10    3  to the right of    0
11    3   to the left of    2
12    3               on   17
13    4   to the left of   13
14    4  to the right of    8
15    5   to the left of   12
16    7           behind   17
17    7  to the right of    3
18    7  to the right of   17
19    7  to the right of    0
20    8   to the left of    1
21    8   to the left of    4
22    8               of   17
23   12  to the right of    5
24   13  to the right of    4
25   13  to the right of   17
26   17   to the left of   13
27   17   to the left of    7
28   17   to the left of    2
29   17      in front of    7