code: def askopenfiles(mode="r", **options):
      
  
      files = askopenfilenames(**options)
      if files:
          ofiles = []
          for filename in files:
              ofiles.append(open(filename, mode))
          files = ofiles
      return files
docs: Ask for multiple filenames and return the open file
      objects
  
      returns a list of open file objects or an empty list if
      cancel selected