need help understanding: converting text to binary

[Eli the Bearded]

In comp.lang.python, Cameron Simpson  <cs at cskk.id.au> wrote:
> On 23Apr2019 20:35, Eli the Bearded <*@eli.users.panix.com> wrote:
>> That feels entirely wrong. I don't know what b'\x9A' means without
>> knowing the character set and character encoding. If the encoding is a
>> multibyte one, b'\x9A' doesn't mean anything on its own. That's why I
>> want to treat it as binary.
> If you don't know the encoding then you don't know you're looking at a 
> hex digit. OTOH, if the binary data contain ASCII data then you do know 
> the encoding: it is ASCII.

Hmmm. Maybe I'm not making myself clear. ASCII "=9a" should decode to
b'\x9A' and it is that binary byte for which I don't know the meaning
and why I don't want to use "text internallly" for as suggested
upthread.

> If that is mixed with other data then you need to know where it 
> starts/stops in order to pull it out to be decoded. The overall data may 
> be a mix, but the bit you're pulling out is encoded text, which you 
> could decode.

I do want to decode it, and possibly compare it for an exact match. And
because there are different possible encodings of the same source data
(consider the trivial case of "=9A" versus "=9a", I don't want to just
keep it in raw form).

Elijah
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not to mention QP versus b64