code: def get(self, key_to_get):
      if key_to_get == "trees_json":
          return self.get_json_trees()
      else:
          raise Exception(
              "Not implemented yet (get key = %s)" % key_to_get
          )
  
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 8 for calling the GBDTDecoder obj's underlying member method code with example usage: obj.get(key_to_get) and returns: self