On which side are the boxes?
The boxes are on the right of the image.
    src        edge_attr  dst
0     0               of    5
1     0   to the left of    1
2     1  to the right of    0
3     1  to the right of    7
4     1  to the right of   13
5     1  to the right of    5
6     1       stacked on   10
7     2   to the left of   11
8     2               of    5
9     2   to the left of   10
10    3  to the right of    5
11    3  to the right of   14
12    4   to the left of   12
13    4   to the left of   10
14    4  to the right of    9
15    4   to the left of   11
16    5   to the left of    1
17    5   to the left of    3
18    5          holding    4
19    6   to the left of   10
20    6   to the left of   12
21    6  to the right of    9
22    6  to the right of   15
23    7               of    4
24    7   to the left of    1
25    7   to the left of   10
26    7   to the left of   11
27    9  to the right of   15
28    9   to the left of    6
29    9   to the left of    4
30   10  to the right of    7
31   10  to the right of    2
32   10  to the right of   12
33   10  to the right of    4
34   10  to the right of    6
35   10  to the right of   11
36   11   to the left of   10
37   11  to the right of   12
38   11  to the right of    2
39   11  to the right of    7
40   11  to the right of    4
41   12   to the left of   10
42   12   to the left of   11
43   12  to the right of    4
44   12  to the right of    6
45   13   to the left of    1
46   14   to the left of    3
47   15   to the left of    6
48   15   to the left of    9