code: def test_compare_faces_empty_lists(self):
      img = api.load_image_file(
          os.path.join(
              os.path.dirname(__file__), "test_images", "biden.jpg"
          )
      )
      face_encoding = api.face_encodings(img)[0]
  
      # empty python list
      faces_to_compare = []
  
      match_results = api.compare_faces(faces_to_compare, face_encoding)
      self.assertEqual(type(match_results), list)
      self.assertListEqual(match_results, [])
  
      # empty numpy list
      faces_to_compare = np.array([])
  
      match_results = api.compare_faces(faces_to_compare, face_encoding)
      self.assertEqual(type(match_results), list)
      self.assertListEqual(match_results, [])
  
imports: import unittest
  import os
  import numpy
  from click.testing import CliRunner
  from face_recognition import api
  from face_recognition import face_recognition_cli
  from face_recognition import face_detection_cli
label_desc: Use image node_id 20 for calling the Test_face_recognition obj's underlying member method code with example usage: obj.test_compare_faces_empty_lists() without return types