def trigger(rank, chunk):
    if (rank == remote_node):
        return cases(chunk, (lambda c: None), (lambda c: (chunk + num_remote_pairs)), (lambda c: (chunk - num_remote_pairs)))
    else:
        return None
def trigger(rank, chunk):
    if (rank == remote_node):
        return cases(chunk, (lambda c: None), (lambda c: (chunk + num_remote_pairs)), (lambda c: (chunk - num_remote_pairs)))
    else:
        return None