docs: def integrate_to_file(what, filename, start_line, end_line):
      """WARNING this is working every second run.. so serious bug
      Integrate content into a file withing "line marks"
      """
  
      try:
          with open(filename) as f:
              lines = f.readlines()
      except IOError:
          lines = []
  
      tmp_file = tempfile.NamedTemporaryFile(delete=False)
  
      lines.reverse()
  
      # first copy before start line
      while lines:
          line = lines.pop()
  
          if line == start_line:
              break
  
          tmp_file.write(line)
  
      # insert content
      tmp_file.write(start_line)
      tmp_file.write(what)
      tmp_file.write(end_line)
  
      # skip until end line
      while lines:
          line = lines.pop()
  
          if line == end_line:
              break
  
      # copy rest
      tmp_file.writelines(lines)
      tmp_file.close()
  
      os.rename(tmp_file.name, filename)