code: def _check_doc_content(doc_tensors, num_pages):
      # 1 doc of 8 pages
      assert len(doc_tensors) == num_pages
      assert all(isinstance(page, np.ndarray) for page in doc_tensors)
      assert all(page.dtype == np.uint8 for page in doc_tensors)
  
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 1 for calling a global function with example usage: _check_doc_content(doc_tensors, num_pages) without return types