code: def test_simple_types(self):
      np.random.seed(42)
      sf = tc.SFrame()
      sf["idx"] = range(_TEST_CASE_SIZE)
      sf["ints"] = np.random.randint(-100000, 100000, _TEST_CASE_SIZE)
      sf["strings"] = sf["ints"].astype(str)
      sf["floats"] = np.random.random(_TEST_CASE_SIZE)
  
      # TODO: nans and infs will break JSON - what should we do about this?
      # sf['nans_and_infs'] = sf['idx'].apply(lambda x: float('nan') if x > 0 else float('inf'))
  
      with tempfile.NamedTemporaryFile(
          mode="w", suffix=".json"
      ) as json_file:
          sf.save(json_file.name, format="json")
          with open(json_file.name) as json_data:
              # will throw if JSON export doesn't work
              loaded = json.load(json_data)
  
file_path: turicreate/src/python/turicreate/test/test_json_export.py
imports: from __future__ import print_function
  from __future__ import division
  from __future__ import absolute_import
  import json
  import numpy
  import struct
  import tempfile
  import unittest
  import turicreate
  import pytest
label_desc: Use image node_id 1 for calling the JSONExporterTest obj's underlying member method code with example usage: obj.test_simple_types() without return types