What is the heart on?
The heart is on the traffic signal.
    src        edge_attr  dst
0     0               of   21
1     1  to the right of    3
2     1  to the right of   11
3     1  to the right of   18
4     2  to the right of   14
..  ...              ...  ...
84   22  to the right of   18
85   22  to the right of   10
86   22  to the right of   15
87   23  to the right of    2
88   23  to the right of    5

[89 rows x 3 columns]