Import words for the wordlist from a given file.

        The file can have a single column with words or be diceware-like
        (two columns).

        Keyword arguments:
        inputfile -- A string with the path to the wordlist file to load, or
        the value 'internal' to load the internal one.
        is_diceware -- True if the file is diceware-like.

def import_words_from_file(self,
                               inputfile: str,
                               is_diceware: bool) -> None:
        """Import words for the wordlist from a given file.

        The file can have a single column with words or be diceware-like
        (two columns).

        Keyword arguments:
        inputfile -- A string with the path to the wordlist file to load, or
        the value 'internal' to load the internal one.
        is_diceware -- True if the file is diceware-like.

        """
        if not Aux.isfile_notempty(inputfile):
            raise FileNotFoundError('Input file does not exists, is not valid '
                                    'or is empty: {}'.format(inputfile))

        self._wordlist_entropy_bits = None
        if is_diceware:
            self._wordlist = self._read_words_from_diceware(inputfile)
        else:
            self._wordlist = self._read_words_from_wordfile(inputfile)