What was used to make the side walk?
The side walk is made of brick.
    src        edge_attr  dst
0     0   to the left of   11
1     0  to the right of    3
2     1   to the left of   20
3     1  to the right of    9
4     1  to the right of    5
..  ...              ...  ...
60   21   to the left of    6
61   21   to the left of   20
62   21   to the left of    5
63   22  to the right of   14
64   22   to the left of   17

[65 rows x 3 columns]