Which side of the image is the knife on?
The knife is on the left of the image.
    src        edge_attr  dst
0     0   to the left of    7
1     0   to the left of    6
2     0   to the left of   12
3     4   to the left of    6
4     4   to the left of   12
5     4   to the left of    7
6     5   to the left of   10
7     6  to the right of    4
8     6  to the right of    0
9     7               on    2
10    7               on    8
11    7  to the right of    4
12    7  to the right of    0
13    7  to the right of   11
14   10  to the right of    5
15   11   to the left of    7
16   12  to the right of    0
17   12  to the right of    4