def record_padding(self, iso_size):
        # type: (int) -> bytes
        '''
        A method to record padding for the ISO hybridization.

        Parameters:
         iso_size - The size of the ISO, excluding the hybridization.
        Returns:
         A string of zeros the right size to pad the ISO.
        '''
        if not self._initialized:
            raise pycdlibexception.PyCdlibInternalError('This IsoHybrid object is not yet initialized')

        return b'\x00' * self._calc_cc(iso_size)[1]
A method to record padding for the ISO hybridization.

        Parameters:
         iso_size - The size of the ISO, excluding the hybridization.
        Returns:
         A string of zeros the right size to pad the ISO.