code: def test_pdf(mock_pdf):
      pages = io.DocumentFile.from_pdf(mock_pdf)
  
      # As images
      num_pages = 2
      _check_doc_content(pages, num_pages)
  
file_path: doctr/tests/common/test_io.py
imports: from io import BytesIO
  from pathlib import Path
  import numpy
  import pytest
  import requests
  from doctr import io
label_desc: Use image node_id 6 for calling a global function with example usage: test_pdf(mock_pdf) without return types