Is the metal sign in front of the tree the shrub is behind of?
Yes, the stop sign is in front of the tree.
    src        edge_attr  dst
0     1  to the right of   12
1     1  to the right of    6
2     1  to the right of    2
3     1  to the right of    8
4     2   to the left of    1
5     2  to the right of   12
6     2   to the left of    9
7     4             near    9
8     4               on    7
9     4               on    2
10    4      in front of    5
11    4      in front of    6
12    5      in front of    9
13    5  to the right of   12
14    5           behind    4
15    6  to the right of   12
16    6   to the left of    1
17    6           behind    4
18    8  to the right of   12
19    8   to the left of    1
20    9             near    4
21    9           behind    5
22    9  to the right of    2
23   10               on    7
24   10               on    2
25   11               on    5
26   12           beside    4
27   12   to the left of    1
28   12   to the left of    8
29   12   to the left of    6
30   12   to the left of    5
31   12   to the left of    2