What are the vehicles in the parking lot called?
The vehicles are cars.
    src        edge_attr  dst
0     0  to the right of    4
1     0  to the right of   12
2     0  to the right of    3
3     0  to the right of    9
4     1   to the left of    8
5     1   to the left of   13
6     1               in    7
7     3  to the right of    6
8     3   to the left of    0
9     3               on    9
10    4   to the left of    0
11    5   to the left of   12
12    5   to the left of    9
13    5  to the right of   10
14    6   to the left of   13
15    6   to the left of    3
16    7   to the left of   13
17    7   to the left of   12
18    8  to the right of   10
19    8               in    7
20    8   to the left of   13
21    8  to the right of    1
22    8   to the left of   12
23    9   to the left of    0
24    9  to the right of    5
25   10   to the left of    8
26   10   to the left of    5
27   11   to the left of   13
28   12   to the left of    0
29   12  to the right of    5
30   12  to the right of   13
31   12  to the right of    7
32   12  to the right of    8
33   13  to the right of    6
34   13  to the right of   11
35   13  to the right of    7
36   13   to the left of   12
37   13  to the right of    8
38   13  to the right of    1