add comment about is-response checking for DDNS

diff --git a/dns/message.py b/dns/message.py
index 85788d84faad0f6e5c67b11443493315ee0c7db9..c5fc3ac8d59ebe212ed97ffa303e5a402092c70d 100644 (file)
--- a/dns/message.py
+++ b/dns/message.py
@@ -239,6 +239,10 @@ class Message:
                 dns.rcode.NOERROR:
             return True
         if dns.opcode.is_update(self.flags):
+            # This is assuming the "sender doesn't include anything
+            # from the update", but we don't care to check the other
+            # case, which is that all the sections are returned and
+            # identical.
             return True
         for n in self.question:
             if n not in other.question: