Mapreduce Send API doesn't work with path_map of add_conditional_edges

[Neet-Nestor]

I noticed that if I defined a path_map in add_conditional_edges call and returns Send objects in the router function, I must specify the original node names in Send instead of the the path name alias defined in the path_map.

I do figure out that according to the doc of Send, it should accept node names only, so I guess it's expected. However, is this an intentional design? Could we support the path names too (as this seems intuitive and consistent for a conditional edge with a path map).

Example code:

def parallel_mapreduce_route(state):
    # return [Send("B", s) for s in state["list"]]    # <--- This will throw error of invalid node names
    return [Send("B_node", s) for s in state["list"]]


if __name__ == '__main__':
    # ...
    graph_builder.add_conditional_edges(
        "A",
        parallel_mapreduce_route,
        {
            "B": "B_node",
            "C": "C_node",
        },
    )