Supongo que es de los viejos tiempos cuando el empaquetado de metadatos no era común entonces. En PEP 8, se recomienda utilizar la variable __version__ de nivel superior para mantener el id de revisión del sistema de control de versiones en uso. Esto data de 2001-05-01. PEP 396 está reemplazando esto para atributos de módulo __version__.
Para __author__ hay una publicación de la lista de distribución de python dev sobre este asunto. Este se remonta a 2001-03-01. El autor cuestiona el uso de __author__: "¿Qué sigue? __cute_signoff__?".
Como no hay mención en las PEP, no tenemos que preocuparnos por __author__. Los metadatos de empaquetado son nuestros amigos de todos modos.
http://mail.python.org/pipermail/python-dev/2001-March/013328.html
Ping just checked in this:
> Log Message:
> Add __author__ and __credits__ variables.
>
>
> Index: tokenize.py
> ===================================================================
> RCS file: /cvsroot/python/python/dist/src/Lib/tokenize.py,v
> retrieving revision 1.19
> retrieving revision 1.20
> diff -C2 -r1.19 -r1.20
> *** tokenize.py 2001/03/01 04:27:19 1.19
> --- tokenize.py 2001/03/01 13:56:40 1.20
> ***************
> *** 10,14 ****
> it produces COMMENT tokens for comments and gives type OP for all operators."""
>
> ! __version__ = "Ka-Ping Yee, 26 October 1997; patched, GvR 3/30/98"
>
> import string, re
> --- 10,15 ----
> it produces COMMENT tokens for comments and gives type OP for all operators."""
>
> ! __author__ = 'Ka-Ping Yee '
> ! __credits__ = 'first version, 26 October 1997; patched, GvR 3/30/98'
>
> import string, re
I'm slightly uncomfortable with the __credits__ variable inserted
here. First of all, __credits__ doesn't really describe the
information given. Second, doesn't this info belong in the CVS
history? I'm not for including random extracts of a module's history
in the source code -- this is more likely than not to become out of
date. (E.g. from the CVS log it's not clear why my contribution
deserves a mention while Tim's doesn't -- it looks like Tim probably
spent a lot more time thinking about it than I did.)
Anothor source of discomfort is that there's absolutely no standard
for this kind of meta-data variables. We've got __version__, and I
believe we once agreed on that (in 1994 or so :-). But __author__?
__credits__? What next -- __cute_signoff__?
Teniendo en cuenta esto probablemente no hay manera de analizar de forma fiable \ _ \ _ autor \ _ \ _ \ _ \ o créditos _ \ _ \ _ atributos. – itsafire