code: def to_x(self, n_id):
      raise NotImplementedError
  
file_path: euler/tf_euler/python/mp_utils/graph_gnn.py
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import tensorflow
  import tf_euler
  from tf_euler.python.euler_ops import mp_ops
  from tf_euler.python.mp_utils import utils
  from tf_euler.python.graph_pool.base_pool import Pooling
label_desc: Use image node_id 5 for calling the GraphGNNNet obj's underlying member method code with example usage: obj.to_x(n_id) without return types