def hyphen(self):
        '''
        Returns ISBN number with segment hypenation
        Data obtained from https://www.isbn-international.org/
        https://www.isbn-international.org/export_rangemessage.xml
        @return: ISBN formated as ISBN13 with hyphens
        '''
        if not ISBN.hyphenRange:
            ISBN.hyphenRange = hyphen.ISBNRange()

        return ISBN.hyphenRange.hyphenformat(self._id)
def hyphen ( self ) : if not ISBN . hyphenRange : ISBN . hyphenRange = hyphen . ISBNRange ( ) return ISBN . hyphenRange . hyphenformat ( self . _id )
Returns ISBN number with segment hypenation
        Data obtained from https://www.isbn-international.org/
        https://www.isbn-international.org/export_rangemessage.xml
        @return: ISBN formated as ISBN13 with hyphens