It Fits Your Brain: the Ninth Annual International Python Conference

The Ninth Annual International Python
Conference was held March 5-8, 2001, at the Long Beach Hilton in
Long Beach, California. Over 300 people attended. This article
covers some observations made by a web developer, with a special
emphasis on the funny things that were said. In case some of you
are unaware, Python is a programming language; its home page is
www.python.org, and a
helpful
tutorial
is posted there.
The Opening KeynoteGuido van Rossum, Python's BDFL (Benevolant Dictator for
Life), introduced the conference theme, "Python Fits Your
Brain"--not everybody's brain, but at least the brains of those who
like it. Guido has always preferred to make the language work well
for its adherents (and especially for himself) rather than try to
please everybody. Not only programmers but also artists, scientists
and teachers are finding Python well suited for their work.PythonLabs, the team of core Python developers, is now
happily situated at Digital Creations, the company that makes Zope.
(Zope is a web application server written in Python; see
their web site.) Those who
fear Python might become straightjacketed to Zope's wishes need not
be concerned. Zope clearly has some clout over Python now, but the
language will remain independent. In fact, the benefits are two-way
because Zope also has some goodies for Python, like the Z Object
Database (for a tutorial, see A. M. Kucheling's
"ZODB/ZEO Programming
Guide").Since last year, some six to eight hundred bugs have been
reported and squashed. Python 2.1 has some nifty new features:
nested scopes, a warnings framework,
pydoc and weak references, to name
a few. Guido is especially excited about pydoc, a program that
finds a module and prints its docstrings and structure in a format
similar to a man page. "You can even run it as a server and point a
web browser at it", he explained.Guide also announced the Python Software Foundation (PSF)
(www.python.org/psf),
a non-profit organization to hold Python's copyright, which is
described as follows: "Modeled after the successful Apache Software
Foundation, the PSF's mandate is to provide educational, legal and
financial resources to the Python community. Responsible for
holding Python's intellectual property, the PSF will also act as an
educational resource, maintain the Python web site and foster
Python user groups."Last year, Guido used the code name "Python 3000" to refer to
a mythical future version that would be perfect but not necessarily
backward-compatible. Since then, the Python team has realized that
a quantum leap is not necessary. All desired changes can be
implemented gradually using the new warnings framework and the
__future__ module to give users a transition period (see
"What's New in Python
2.1" for more information).He then introduced Python Enhancement Proposals (PEPs) (see
python.sourceforge.net/peps).
A PEP document proposes one change to the language or to the
standard library, and it serves as the definitive summary of the
arguments for and against it. This replaces the disorganized
free-for-all under which past language enhancements were debated
(and then lost in the forest of newsgroup archives). It works
great, Guido says, when somebody gets a bright idea that was
rejected six months ago, "except when it's
your bright idea that's being
rejected".He was so excited about
Pippy,
a port of Python 1.5.2+ for the Palm Pilot, that he got a PalmOS
3.5 upgrade just because it was "so cool". He thinks Python is a
perfect match for small end embedded platforms. To facilitate this,
the Python team must be extra diligent to avoid code bloat so that
Python can run in 8MB of RAM with space for application code and
data.State of the ZopePaul Everett, head of Digital Creations (DC), opened the Zope
track of presentations at the conference. "Zope is finally
maturing", he said. 2001 will be the Year of the Zope Books; five
will be published by the end of the year. DC has three goals for
Zope this year: increase its public profile, ease the learning
curve and increase its use in enterprise situations."The Python language combines power and simplicity", he said.
"Zope has at least half of that." Zope's main users are developers
now, so DC is moving Zope to a more component-centric and
developer-friendly architecture. Three major concepts that looked
great at the beginning but have since shown their limitations
(acquisition, inheritance and DTML) are being supplanted by other
concepts that contain fewer "gotchas".Webware2001 is also the year of Zope Alternatives. My favorite
discovery was
Webware. Chuck
Esterbrook developed this modular web application server out of
frustration with the monolithic nature of Zope (see Chuck's
presentation
for an overview). The main component is WebKit, which allows Python
packages to be servlets. Here's a minimum servlet:

from WebKit.Page import Page
class index(Page):
    def title(self): # This will go into the HTML <TITLE> tag.
        return "Important Message"
    def writeBody(self):
        self.writeln(" This web site is not here yet.")

You can call this "index.py" and invoke it in the browser as
index.py, index or even as the directory. The file must contain a
class with the same name as the file, and this class is normally a
subclass of Page. CGI parameters and cookies are as simple
as:

        req = self.request()
        fname = req.field('fname')
        bgcolor = req.cookie('bgcolor', '#FFFFFF') # With default.

You even get a session object for free:

        sess = self.session()
        name = sess.value('name')
        sess.setValue('x', 5)

The application caches servlet instances for later reuse. It
interacts with Apache or AOLserver via a CGI interface or a web
server module (e.g., mod_python). Two other plug-ins deserve
mention. Python Server Pages is for those who prefer embedding
Python commands in HTML files à la ASP or PHP. MiddleKit is
an object-oriented intermediary for database access.Other Presentations and ExhibitsI wish I had space to discuss some of the other talks. Eric
Raymond presented CML2, his Linux kernel configuration system.
Others talked about internationalizing Mailman using GNU gettext,
weak references, writing Microsoft .NET programs in Python, etc.
One notable module mentioned is
pyperl),
which allows your script to call Perl functions.In the hallway were vendor exhibits, including ActiveState's
Python
Cookbook (a free interactive FAQ), and the Toilet Paper
display.Toilet
Paper is an automated water closet. No, there wasn't a loo
in the hallway, just a diagram of the privy. A 486 computer running
Slackware sits alongside the porcelain bowl. It detects visitors
outside via a motion detector and has sensors for toilet seat
position, light switch position, etc., and then plays appropriate
music for each state. It fetches selected web pages, extracts the
headlines and displays them on an LCD screen. Toilet also has an
external web interface to request songs, report on its usage
history (scary) and send messages to the LCD screen.Closing KeynoteBruce Eckel is the person who invented the "Python Fits Your
Brain" slogan as well as last year's "Life is Better Without
Braces". He's also a well-known C++ and Java design consultant. In
his closing keynote, Bruce presented the top ten reasons why he
loves Python:(See
the
Powerpoint slides from Bruce's presentation.)10. Reduced clutter.9. It's not
backward-compatible with other languages. (This came with some
hilarious one-liners: "C++'s backward compatibility with C is both
its strength and its bane"; "Java causes repetitive-strain
syndrome"; "Perl is compatible with every hacky syntax of every
UNIX tool ever invented"; "C# and Microsoft .NET are
backward-compatible with Microsoft's previous marketing campaigns";
and "Javascript is not even compatible with itself".)8. It doesn't value
performance over my productivity.7. It doesn't treat me like
I'm stupid. Java insists operator overloading is bad because you
can make ugly code with it. Bruce observes, "And we all know
there's no ugly Java code out there."6. I don't have to wait
forever for a full implementation of the language.5. It doesn't make
assumptions about how we discover errors.4. Marketing people are not
involved in it (yet).3. I don't have to type so
much. But what I do type is the right
typing.2. My guesses are usually
right.1. Python helps me focus on
my concepts rather than on fighting with the language.His idea for the next Python slogan? "No warranty, not fit
for any particular purpose." We'll see about that next year.Conference proceedings and slides have been posted to the
Python9 web
site.Mike Orr writes web
applications at SSC, edits Linux Gazette and
does other sysadmin stuff. He doesn't usually write articles, but
he makes an exception for Python because it's so cool.

email: mso@ssc.com