What is before the tree?
The bus is in front of the tree.
    src        edge_attr  dst
0     0               in    1
1     1   to the left of    6
2     1  to the right of    5
3     1  to the right of   10
4     1      in front of   11
5     1   to the left of   11
6     2  to the right of    8
7     2  to the right of   10
8     2           inside    1
9     3  to the right of   10
10    5   to the left of    9
11    5   to the left of    1
12    6  to the right of    1
13    6  sitting next to    9
14    7   to the left of   11
15    7  on the front of    1
16    8  to the right of   10
17    8   to the left of    2
18    9  to the right of    5
19    9             near   10
20   10   to the left of   12
21   10   to the left of    2
22   10   to the left of    8
23   10   to the left of    3
24   10             near    9
25   10   to the left of    1
26   11           behind    1
27   11  to the right of    7
28   11  to the right of    1
29   12  to the right of   10