Do you see either balls or tennis rackets in the image?
Yes, there is a ball.
    src        edge_attr  dst
0     0  to the right of   13
1     0   to the left of    9
2     2   to the left of   13
3     2  to the right of   11
4     2  to the right of    3
5     3   to the left of    2
6     3   to the left of   11
7     4   to the left of    9
8     6               in    7
9     9  to the right of    4
10    9  to the right of    0
11   11  to the right of    3
12   11   to the left of    2
13   11   to the left of   13
14   13   to the left of    0
15   13  to the right of   11
16   13  to the right of    2