code: def pdftotext(filename):
      """
      ```
      Use pdftotext program to convert PDF to text string.
      :param filename: of PDF file
      :return: text from file, or empty string if failure
      ```
      """
      output = Popen(
          ["pdftotext", "-q", filename, "-"], stdout=PIPE
      ).communicate()[0]
      # None may indicate damage, but convert for consistency
      return "" if output is None else output
  
imports: from subprocess import DEVNULL, PIPE, Popen
  from ..imports import *
label_desc: Use image node_id 5 for calling a global function with example usage: pdftotext(filename) and returns: unknown