Why use x_j? not x_i in EGraphSage class

[zhdhfhd33]

Hi, I am learning about grape for data imputation I think that the paper's pseudo code and python implementation is not matching. Is it right to use x_i instead of x_j? for consistency of codes? x_j : source x_i : destination

please let me known if I understand grape wrong way.

[zhdhfhd33]

above code is in egsage.py - EGraphSage.messgae() function