What is on the roof in the picture?
The tiles are on the roof.
    src        edge_attr  dst
0     0   to the left of   21
1     0               in    1
2     0   to the left of   20
3     2   to the left of   21
4     2   to the left of   11
5     3  to the right of   20
6     3  to the right of   10
7     5   to the left of   18
8     5   to the left of   16
9     9   to the left of   18
10    9   to the left of   16
11   10   to the left of   17
12   10   to the left of    3
13   10   to the left of   21
14   11  to the right of    2
15   12  to the right of   22
16   13  to the right of   21
17   13               in    1
18   13  to the right of   17
19   14  to the right of   19
20   15   to the left of   21
21   15   to the left of   23
22   15               on    2
23   16  to the right of    5
24   16  to the right of    9
25   17  to the right of   20
26   17  to the right of   10
27   17   to the left of   13
28   18  to the right of    5
29   18  to the right of    9
30   19   to the left of   14
31   20   to the left of   21
32   20   to the left of   17
33   20   to the left of    3
34   20  to the right of    0
35   21  to the right of    2
36   21  to the right of   10
37   21  to the right of    0
38   21  to the right of   20
39   21  to the right of   23
40   21   to the left of   13
41   21  to the right of   15
42   22   to the left of   12
43   23  to the right of   15
44   23   to the left of   21