Is there either a bus or a train that is not blue?
No, there is a bus but it is blue.
    src        edge_attr  dst
0     0  to the right of    1
1     0  to the right of    3
2     1   to the left of    5
3     1   to the left of    7
4     1   to the left of    0
5     1   to the left of    3
6     2   to the left of    7
7     3       walking by    7
8     3   to the left of    7
9     3  to the right of    1
10    3   to the left of    5
11    3   to the left of    0
12    3          next to    7
13    5  to the right of    1
14    5  to the right of    3
15    7  to the right of    2
16    7  to the right of    3
17    7  to the right of    1
18    7             near    3