code: def get_all_edges(self):
      edge_list = []
      visited = set()
      self.get_all_edge_helper(visited, edge_list)
      return edge_list
  
imports: from __future__ import print_function
  from __future__ import division
  from __future__ import absolute_import
  import turicreate
  import unittest
  import json
  import random
  import numpy
  import pytest
label_desc: Use image node_id 12 for calling the GBDTNode obj's underlying member method code with example usage: obj.get_all_edges() and returns: edge_list