Which kind of vehicle is parked on the roadside?
The vehicles are cars.
    src        edge_attr  dst
0     0  to the right of    5
1     1  to the right of   11
2     2  to the right of    7
3     2  to the right of   14
4     3   to the left of    4
5     3   to the left of    8
6     3   to the left of    7
7     4        parked on    9
8     4  to the right of    3
9     4   to the left of   11
10    4   to the left of    7
11    5               on   12
12    5   to the left of    0
13    6     hanging from    5
14    7  to the right of    8
15    7   to the left of    2
16    7  to the right of    3
17    7  to the right of    4
18    8  to the right of    3
19    8               on   11
20    8   to the left of    7
21    9  to the right of   10
22   10   to the left of    9
23   11  to the right of    4
24   11   to the left of    1
25   14   to the left of    2