code: def test_single_image(self):
      # Predict should work on a single image and product a list of dictionaries
      # (we set confidene threshold to 0 to ensure predictions are returned)
      pred = self.model.predict(
          self.sf[self.feature][0], confidence_threshold=0
      )
      self.assertTrue(isinstance(pred, list))
      self.assertTrue(isinstance(pred[0], dict))
  
imports: from __future__ import print_function
  from __future__ import division
  from __future__ import absolute_import
  import unittest
  import pytest
  from .None import util
  import turicreate
  import tempfile
  import numpy
  import platform
  import pytest
  import sys
  import os
  from turicreate.toolkits._main import ToolkitError
  from turicreate.toolkits._internal_utils import _raise_error_if_not_sarray, _mac_ver
  from six import StringIO
label_desc: Use image node_id 18 for calling the ObjectDetectorTest obj's underlying member method code with example usage: obj.test_single_image() without return types