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