Python in a Nutshell, 4th Edition

Chapter 21. Email, MIME, and Other Network Encodings

What travels on a network are streams of bytes, also known in networking jargon as octets. Bytes can, of course, represent text, via any of several possible encodings. However, what you want to send over the network often has more structure than just a stream of text or bytes. The Multipurpose Internet Mail Extensions (MIME) and other encoding standards bridge the gap, by specifying how to represent structured data as bytes or text. While often originally designed for email, such encodings are also used on the web and in many other networked systems. Python supports such encodings through various library modules, such as base64, quopri, and uu (covered in “Encoding Binary Data as ASCII Text”), and the modules of the email package (covered in the following section). These encodings allow us, for example, to seamlessly create messages in one encoding containing attachments in another, avoiding many awkward tasks along the way.

MIME and Email Format Handling

The email package handles parsing, generation, and manipulation of MIME files such as email messages, Network News Transfer Protocol (NNTP) posts, HTTP interactions, and so on. The Python standard library also contains other modules that handle some parts of these jobs. However, the email package offers a complete and systematic approach to these important tasks. We suggest you use email, not the older modules that partially overlap with parts of email’s functionality. email ...