On which side of the image is the train?
The train is on the left of the image.
     src        edge_attr  dst
0      0   to the left of   12
1      0   to the left of   17
2      0  to the right of    9
3      0  to the right of    4
4      0  to the right of   18
..   ...              ...  ...
97    19  to the right of    9
98    19   to the left of   17
99    19  to the right of    7
100   19   to the left of    2
101   19  to the right of   16

[102 rows x 3 columns]