Is there a clock on the roof?
Yes, there is a clock on the roof.
    src        edge_attr  dst
0     0   to the left of    2
1     1   to the left of    2
2     2  to the right of    7
3     2  to the right of    3
4     2  to the right of    1
5     2  to the right of    0
6     3   to the left of    5
7     3   to the left of    2
8     4   to the left of   11
9     4   to the left of    6
10    5  to the right of    7
11    5  to the right of    3
12    6  to the right of    7
13    6  to the right of    4
14    7               on    8
15    7   to the left of    5
16    7   to the left of    2
17    7   to the left of   11
18    7   to the left of    6
19    9               on   10
20   11  to the right of    7
21   11  to the right of    4