Is there any cow on the road?
No, there is a van on the road.
    src        edge_attr  dst
0     0   to the left of   14
1     0  to the right of   12
2     0   to the left of   15
3     0   to the left of    3
4     0   to the left of    1
5     0   to the left of    7
6     0   to the left of    6
7     0               on    2
8     1   to the left of   11
9     1  to the right of    0
10    1               on    2
11    3  to the right of    0
12    3  to the right of    7
13    3  to the right of    6
14    3  to the right of   15
15    4   to the left of   13
16    5   to the left of   13
17    6  to the right of    0
18    6   to the left of    3
19    6  to the right of    7
20    6   to the left of   15
21    7  to the right of    0
22    7   to the left of    3
23    7   to the left of    6
24    7   to the left of   15
25    9   to the left of   11
26   11  to the right of    9
27   11  to the right of    1
28   11               on    2
29   12   to the left of    0
30   13  to the right of    5
31   13  to the right of    4
32   14  to the right of    0
33   15   to the left of    3
34   15  to the right of    0
35   15  to the right of    6
36   15  to the right of    7