What color is the pipe?
The pipe is black.
    src        edge_attr  dst
0     0   to the left of    6
1     0   to the left of    9
2     2  to the right of   11
3     2   to the left of    5
4     3  to the right of    5
5     3  to the right of    8
6     4   to the left of    5
7     4  to the right of   11
8     5  to the right of    2
9     5   to the left of    3
10    5  to the right of    4
11    6               on    9
12    6  to the right of    9
13    6  to the right of    0
14    7            below   10
15    8   to the left of    3
16    8               on    9
17    9   to the left of    6
18    9  to the right of    0
19   11   to the left of    2
20   11   to the left of    4