code: def read_dir(directory):
      '''Returns the text of all files in a directory.'''
      content = dir_list(directory)
      text = ''
      for filename in content:
          text += read_file(directory + '/' + filename)
          text += ' '
      return texf read_dir(directory):
      '''Returns the text of all files in a directory.'''
      content = dir_list(directory)
      text = ''
      for filename in content:
          text += read_file(directory + '/' + filename)
          text += ' '
      return text
docs: Returns the text of all files in a directory.