How to use the pycdlib.rockridge.RRRRRecord function in pycdlib

def test_rrrrrecord_record_not_initialized():
    rr = pycdlib.rockridge.RRRRRecord()
    with pytest.raises(pycdlib.pycdlibexception.PyCdlibInternalError) as excinfo:
        rr.record()
    assert(str(excinfo.value) == 'RR record not initialized')

def test_rrrrrecord_append_field_invalid_field():
    rr = pycdlib.rockridge.RRRRRecord()
    rr.new()
    with pytest.raises(pycdlib.pycdlibexception.PyCdlibInternalError) as excinfo:
        rr.append_field('AA')
    assert(str(excinfo.value) == 'Unknown RR field name AA')

def test_rrrrrecord_append_field_nm():
    rr = pycdlib.rockridge.RRRRRecord()
    rr.new()
    rr.append_field('NM')
    assert(rr.rr_flags == 0x8)

def test_rrrrrecord_record():
    rr = pycdlib.rockridge.RRRRRecord()
    rr.new()
    rec = rr.record()
    assert(rec == b'RR\x05\x01\x00')

def test_rrrrrecord_append_field_sl():
    rr = pycdlib.rockridge.RRRRRecord()
    rr.new()
    rr.append_field('SL')
    assert(rr.rr_flags == 0x4)

Parameters:
         rrstr - The string to parse the record out of.
        Returns:
         Nothing.
        '''
        if self._initialized:
            raise pycdlibexception.PyCdlibInternalError('RR record already initialized')

        (su_len, su_entry_version_unused,
         self.rr_flags) = struct.unpack_from(self.FMT, rrstr[:5], 2)

        # We assume that the caller has already checked the su_entry_version,
        # so we don't bother.

        if su_len != RRRRRecord.length():
            raise pycdlibexception.PyCdlibInvalidISO('Invalid length on rock ridge extension')

        self._initialized = True

# In reality, this can never happen.  If the RR record pushes
                    # us over the DR limit, then there is no room for a CE record
                    # either, and we are going to fail.  We leave this in place
                    # both for consistency with other records and to keep mypy
                    # happy.
                    return -1
                self.dr_entries.ce_record.add_record(thislen)
                self.ce_entries.sp_record = new_sp
            else:
                curr_dr_len += thislen
                self.dr_entries.sp_record = new_sp

        # For RR Record
        rr_record = None
        if self.rr_version == '1.09':
            rr_record = RRRRRecord()
            rr_record.new()
            thislen = RRRRRecord.length()
            if curr_dr_len + thislen > ALLOWED_DR_SIZE:
                if self.dr_entries.ce_record is None:
                    # In reality, this can never happen.  If the RR record pushes
                    # us over the DR limit, then there is no room for a CE record
                    # either, and we are going to fail.  We leave this in place
                    # both for consistency with other records and to keep mypy
                    # happy.
                    return -1
                self.dr_entries.ce_record.add_record(thislen)
                self.ce_entries.rr_record = rr_record
            else:
                curr_dr_len += thislen
                self.dr_entries.rr_record = rr_record

recname = rtype.decode('utf-8').lower() + '_record'
                if self.has_entry(recname):
                    raise pycdlibexception.PyCdlibInvalidISO('Only single %s record supported' % (rtype.decode('utf-8')))

            if rtype == b'SP':
                if left < 7 or not is_first_dir_record_of_root:
                    raise pycdlibexception.PyCdlibInvalidISO('Invalid SUSP SP record')

                # OK, this is the first Directory Record of the root
                # directory, which means we should check it for the SUSP/RR
                # extension, which is exactly 7 bytes and starts with 'SP'.

                entry_list.sp_record = RRSPRecord()
                entry_list.sp_record.parse(recslice)
            elif rtype == b'RR':
                entry_list.rr_record = RRRRRecord()
                entry_list.rr_record.parse(recslice)
            elif rtype == b'CE':
                entry_list.ce_record = RRCERecord()
                entry_list.ce_record.parse(recslice)
            elif rtype == b'PX':
                entry_list.px_record = RRPXRecord()
                px_record_length = entry_list.px_record.parse(recslice)
            elif rtype == b'PD':
                pd = RRPDRecord()
                pd.parse(recslice)
                entry_list.pd_records.append(pd)
            elif rtype == b'ST':
                entry_list.st_record = RRSTRecord()
                entry_list.st_record.parse(recslice)
            elif rtype == b'ER':
                entry_list.er_record = RRERRecord()