def backness(self, value):
        """
        Set the backness of the vowel.

        :param str value: the value to be set
        """
        if (value is not None) and (not value in DG_V_BACKNESS):
            raise ValueError("Unrecognized value for backness: '%s'" % value)
        self.__backness = value
def backness ( self , value ) : if ( value is not None ) and ( not value in DG_V_BACKNESS ) : raise ValueError ( "Unrecognized value for backness: '%s'" % value ) self . __backness = value
Set the backness of the vowel.

        :param str value: the value to be set