What is the animal to the left of the cow that wears a collar?
The animal is a bull.
    src        edge_attr  dst
0     0  to the right of    2
1     2  to the right of   11
2     2   to the left of    0
3     3          wearing   10
4     3  to the right of    6
5     3  to the right of   11
6     3  to the right of    7
7     5               of    8
8     6  to the right of   11
9     6   to the left of    3
10    6               of    2
11    7   to the left of   10
12    7   to the left of    3
13    9               of    7
14   10           around    3
15   10  to the right of    7
16   11   to the left of    2
17   11   to the left of    6
18   11   to the left of    3