code: def test_qr_code_detector(mock_image_folder):
      detector = BarCodeDetector()
      for img in os.listdir(mock_image_folder):
          image = DocumentFile.from_images(
              os.path.join(mock_image_folder, img)
          )[0]
          barcode = detector(image)
          assert len(barcode) == 0
  
imports: import os
  from doctr.io import DocumentFile
  from doctr.models.artefacts import BarCodeDetector, FaceDetector
label_desc: Use image node_id 1 for calling a global function with example usage: test_qr_code_detector(mock_image_folder) without return types