code: def extract_text(self):
      if len(self.processed_pages) > 0:
          for page in self.processed_pages:
              new = page
              text = new.extract_text()
              self.page_content.append(text)
      else:
          raise Exception("You must run `process()` first.")
  
file_path: doc2text/doc2text/__init__.py
imports: import os
  import mimetypes
  import PyPDF2
  import PythonMagick
  import cv2
  from .page import Page
label_desc: Use image node_id 4 for calling the Document obj's underlying member method code with example usage: obj.extract_text() without return types