@@ -26,6 +26,7 @@
 import socket
 from typing import TYPE_CHECKING, Any, cast
 
+from ._exceptions import AbstractMethodException
 from ._utils.net import _is_v6_address
 from ._utils.time import current_time_millis
 from .const import _CLASS_MASK, _CLASS_UNIQUE, _CLASSES, _TYPE_ANY, _TYPES
@@ -156,7 +157,7 @@ def __repr__(self) -> str:
         )
 
 
-class DNSRecord(DNSEntry):
+class DNSRecord(DNSEntry):  # noqa: PLW1641
     """A DNS record - like a DNS entry, but has a TTL"""
 
     __slots__ = ("created", "ttl")
 
@@ -311,6 +311,7 @@ def _read_string(self, length: _int) -> bytes:
         return info
 
     def _read_others(self) -> None:
+        """Read the answer, authority and additional sections."""
         self._did_read_others = True
         buf = self._buf
         answers = self._answers
 
@@ -65,11 +65,10 @@ cdef class DNSOutgoing:
     cdef cython.bint _write_question(self, DNSQuestion question)
 
     @cython.locals(
-        chunk=cython.bytes,
         data_length_before=cython.uint,
         size_before=cython.uint,
         length_index=cython.uint,
-        rdata_length=cython.uint,
+        rdata_size_start=cython.uint,
     )
     cdef cython.bint _write_record(self, DNSRecord record, double now)
 
 
@@ -335,11 +335,9 @@ def _write_record(self, record: DNSRecord_, now: float_) -> bool:
         self._write_ttl(record, now)
         length_index = len(self.data)
         self.write_short(0)  # placeholder for the rdata length
+        rdata_size_start = self.size
         record.write(self)
-        rdata_length = 0
-        for chunk in self.data[length_index + 1 :]:
-            rdata_length += len(chunk)
-        self._replace_short(length_index, rdata_length)
+        self._replace_short(length_index, self.size - rdata_size_start)
         return self._check_data_limit_or_rollback(data_length_before, size_before)
 
     def _check_data_limit_or_rollback(self, start_data_length: int_, start_size: int_) -> bool:
 
@@ -457,6 +457,7 @@ def test_questions_do_not_end_up_every_packet(self):
 
 class PacketForm(unittest.TestCase):
     def test_transaction_id(self):
+        """Multicast DNS messages carry transaction id 0 (RFC 6762 section 18.1)."""
         generated = r.DNSOutgoing(const._FLAGS_QR_QUERY)
         bytes = generated.packets()[0]
         id = bytes[0] << 8 | bytes[1]