From: albert@einstein.com
To: marie@curie.com
Subject: Test Subject
Date: Mon, 01 Jan 2024 14:00:00 +0000
MIME-Version: 1.0
Content-Type: multipart/alternative;
 boundary="RZcCpBhV4GEzm8ETTVblOuzZ8bwGzGVyjkQfGTMt"

--RZcCpBhV4GEzm8ETTVblOuzZ8bwGzGVyjkQfGTMt
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit

This is a test message (plaintext).
--RZcCpBhV4GEzm8ETTVblOuzZ8bwGzGVyjkQfGTMt
Content-Type: text/html; charset=utf-8
Content-Transfer-Encoding: 7bit

<p>This is a test message (html).</p>
--RZcCpBhV4GEzm8ETTVblOuzZ8bwGzGVyjkQfGTMt--