code: def line_type(line:str) -> str:
      
      for regex, ltype in LINE_TYPES.items():
          if re.fullmatch(regex, line):
              return ltype
      raise ValueError("Input line \"{}\" is not bubble formatted".format(line))
docs: Give type of input line, as defined in LINE_TYPES
  
      >>> line_type('IN\\ta\\tb')
      'IN'
      >>> line_type('')
      'EMPTY'