python3-webencodings binary package in Ubuntu Focal amd64

 In order to be compatible with legacy web content when interpreting something
 like Content-Type: text/html; charset=latin1, tools need to use a particular
 set of aliases for encoding labels as well as some overriding rules. For
 example, US-ASCII and iso-8859-1 on the web are actually aliases for
 windows-1252, and an UTF-8 or UTF-16 BOM takes precedence over any other
 encoding declaration. The Encoding standard defines all such details so that
 implementations do not have to reverse-engineer each other.
 .
 This module has encoding labels and BOM detection, but the actual
 implementation for encoders and decoders is Python’s.
 .
 This package provides the module for Python 3.

Source package