What do the building and the clock have in common?
The color, both the building and the clock are white.
    src        edge_attr  dst
0     0  to the right of    9
1     1  to the right of    7
2     2               by   12
3     2               on    9
4     2               on   11
5     2   to the left of    9
6     2   to the left of    4
7     2   to the left of   11
8     4               on    9
9     4  to the right of    2
10    6  to the right of    9
11    7   to the left of    1
12    9   to the left of    0
13    9   to the left of    6
14    9  to the right of    2
15    9   to the left of   11
16    9   to the left of   10
17   10  to the right of    9
18   11  to the right of    9
19   11  to the right of    2