What is the color of the propeller?
The propeller is dark.
    src        edge_attr  dst
0     0   to the left of    8
1     1   to the left of    2
2     1             near    2
3     2  to the right of    8
4     2  to the right of    1
5     2             near    1
6     3   to the left of    9
7     4               on    5
8     6               on    5
9     7   to the left of   10
10    8   to the left of   20
11    8  to the right of    0
12    8   to the left of    2
13    9   to the left of   17
14    9   to the left of   15
15    9  to the right of   11
16    9  to the right of    3
17   10  to the right of   17
18   10  to the right of   15
19   10  to the right of    7
20   10  to the right of   12
21   11   to the left of   17
22   11   to the left of    9
23   12   to the left of   10
24   12  to the right of   17
25   12   to the left of   13
26   12  to the right of   15
27   13  to the right of   12
28   14               of    6
29   14   to the left of   18
30   15   to the left of   18
31   15  to the right of    9
32   15   to the left of   10
33   15   to the left of   12
34   15  to the right of   17
35   17  to the right of   11
36   17   to the left of   15
37   17  to the right of    9
38   17   to the left of   18
39   17   to the left of   10
40   17   to the left of   12
41   18  to the right of   14
42   18  to the right of   15
43   18  to the right of   17
44   20  to the right of    8
45   20               of    6