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## 5.39.0

**`(feat):`** XML (TwiML) models can now carry XML comments. `comment(text)` adds `<!--text-->` inside the element at
its position in the ordered content (interleaved with `add_text` segments and child elements), while
`comment_before(text)` / `comment_after(text)` render a comment immediately before or after the element
itself (as a sibling in its parent, or around the root element after the XML declaration). Comments in
parsed documents are preserved by `from_xml` and round-trip through `to_xml`; `XmlElement.add_comment`
and the new `XmlComment` node expose the same for untyped elements.

## 5.38.0

**`(feat):`** Generate a unit test file per XML-encoded (TwiML) type alongside the models, covering
fromXml/toXml round trips, escaping, unknown attributes/children, open enum passthrough,
child ordering, and rejection of malformed XML, wrong root elements and DOCTYPE declarations.