What is in front of the building?
The bus is in front of the building.
    src        edge_attr  dst
0     0               on   17
1     0      in front of   10
2     1  to the right of   21
3     2               on   20
4     2   on the side of   10
5     6  to the right of    8
6     6  to the right of   14
7     7               on   21
8     7   to the left of   17
9     8  to the right of   14
10    8   to the left of    6
11   10           behind    0
12   11  to the right of   20
13   14   to the left of    8
14   14  to the right of   20
15   14   to the left of    6
16   17  to the right of    7
17   20   to the left of   14
18   20   to the left of   11
19   21   to the left of    1