Is there either any stop sign or skateboard in this photograph?
No, there are no skateboards or stop signs.
    src        edge_attr  dst
0     0      in front of    1
1     1  to the right of    4
2     1           behind    0
3     2  to the right of    3
4     3   to the left of    2
5     4   to the left of    8
6     4   to the left of   13
7     4   to the left of    1
8     5   to the left of    6
9     6  to the right of    5
10    8  to the right of    4
11    8  to the right of   13
12   10  to the right of   11
13   11   to the left of   10
14   12  to the right of   15
15   13   to the left of    8
16   13  to the right of    4
17   15   to the left of   12