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I'm familiar with LAMP systems and have been programming mostly in PHP for the past 4 years. I'm learning Python and playing around with Nginx a little bit.
We're working on a project website which will handle a lot of http handle requests, stream videos(mostly from a provider like youtube or vimeo). My colleague has experience with OpenBSD and has insisted that we use it as an alternative to linux.
The reason that we want to use OpenBSD is that it's well known for
it's security.
The reason we chose Python is that it's fast.
The reason we want to use Nginx is that it's known to be able to
handle more http request when compared to Apache.
The reason we want to use NoSQL is that MySQL is known to have
problems in scalability when the databases grows.
We want the web pages to load as fast as possible (caching and cdn's will be used) using the minimum amount of hardware possible. That's why we want to use ONPN (OpenBSD,Nginx,Python,Nosql) instead of the traditional LAMP (Linux,Apache,Mysql,PHP).
We're not a very big company so we're using opensource technologies. Any suggestion is appreciated on how to use these software as a platform and giving hardware suggestions is also appreciated. Any criticism is also welcomed.
My advice - if you don't know how to use these technologies - don't do it. Few servers will cost you less than the time spent mastering technologies you don't know. If you want to try them out - do it. One by one, not everything at once. There is no magic solution on how to use them.
I agree with wdev, the time it takes to learn this is not worth the money you will save. First of all, MySQL databases are not hard to scale. WordPress utilizes MySQL databases, and some of the world's largest websites use MySQL (google for a list). I can also say the same of linux and PHP.
If you design your site using best practices (CSS sprites) Apache versus Nginx will not make a considerable difference in load times if you utilize a CDN and best practices (caching, gzip, etc).
I strongly urge you to reconsider your decisions. They seem very ill-advised.
I'm super new to programming and I've been using appengine to help me learn python and general coding. I'm getting better quickly and I'm loving it all the way :)
Appengine was awesome for allowing me to just dive into writing my app and getting something live that works (see http://www.7bks.com/). But I'm realising that the longer I continue to learn on appengine the more I'm constraining myself and locking myself into a single system.
I'd like to move to developing on full django (since django looks super cool!). What are my next steps? To give you a feel for my level of knowledge:
I'm not a unix user
I'm not familiar with command line controls (I still use appengine/python completely via the appengine SDK)
I've never programmed in anything other than python, anywhere other than appengine
I know the word SQL, but don't know what MySQL is really or how to use it.
So, specifically:
What are the skills I need to learn to get up and running with full django/python?
If I'm going to host somewhere else I suppose I'll need to learn some sysadmin type skills (maybe even unix?). Is there anywhere that offers easy hosting (like appengine) but that supports django?
I hear such great things about heroku I'm considering switching to RoR and going there
I appreciate that I'm likely not quite ready to move away from appengine just yet but I'm a fiercely passionate learner (http://www.7bks.com/blog/179001) and would love it if I knew all the steps I needed to learn so I could set about learning them. At the moment, I don't even know what the steps are I need to learn!
Thank you very much. Sorry this isn't a specific programming question but I've looked around and haven't found a good how-to for someone of my level of experience and I think others would appreciate a good roadmap for the things we need to learn to get up and running.
Thanks,
Tom
PS - if anyone is in London and fancies showing me the ropes in person that would be super awesome :)
First up, you can benefit by doing some RoR work by learning a new language. However, I don't know if that'll be entirely beneficial to you right now since you still are learning. I'd stick with Python and Django (or AppEngine) for the moment, until you can grasp some of the more advance concepts. Then, by all means, learning new languages will be fantastic.
As for moving to Django from AppEngine. There isn't a whole lot that's different. The way you define models is similar, but has different types for the definition. As you mentioned, hosting is another consideration.
There should be plenty of hosting options (mod_wsgi is what you're after) based on Apache. Django in particular has seen quite a bit of popularity, and hosting usually springs up for popular frameworks.
I don't think you'll need to know too much sysadmin stuff. This will all depend on the kind of hosting you can find. Same goes for the database. Hosting providers usually offer databases preconfigured so you shouldn't need to worry about that too much.
Django, along with many other frameworks, provide an ORM (Object Relational Mapper) which abstracts away having to write SQL, by calling methods on objects and accessing their properties. I'd advise learning a little bit of SQL to understand it at a bare minimum though.
The Django tutorial is excellent! If you decide to go the Django route, I'd highly recommend working through the entire thing. A development server comes bundled, so you can try out your work instantly without worrying about a provider. Once you have something you want to share with the world, you can worry about hosting then.
I started off using Windows for Django development and it was quite easy. The amount of command line work you need to do is minimal. Really. Not something you need to worry about, as the tutorial covers all 4 or so commands you need to know.
Django hosting provides links to hosting providers, though I'm not sure how up to date that list is.
Getting started in Django is pretty simple. Once you want to host it, there's a bit more work involved - but that can come later. The friction is minimal. Follow the tutorial, it will take you through running the server, setting up the database (a free one comes bundled), and coding your first app.
What makes you think you're being locked into a single platform? Did you know that Google's App Engine SDK is open source? Also, there are universities and other organizations who are working on building platforms that will use the App Engine SDK outside of the context of Google? Amazon EC2 is also capable of running App Engine's SDK in a limited capacity. I'd say lock-in is perhaps not the right word to use.
Additionally, I believe AppEngine is going to continue to improve as time goes on. Google is the leader of the Internet; they've done great things and will continue to do so. I believe that anyone who sticks with their platform as a service will experience these great benefits in the years to come.
If your reasoning for moving is purely academic, I'd suggest starting a new project. Moving off of AppEngine's SDK is similar to switching from one framework to another on an already-built application. Like with any framework or platform, there are dependencies that must be dealt with in order to successfully migrate the app from platform A to platform B.
django-nonrel makes it possible to run Django on Google AppEngine: http://www.allbuttonspressed.com/projects/django-nonrel
Beside that there exists a couple of cloud offers like djangy https://www.djangy.com/
With both options you can focus on Django and Python programming and don't have to care about the sysadmin stuff.
On the django homepage there is a very good tutorial to get started with django development: http://docs.djangoproject.com/en/1.2/intro/tutorial01/
What are the skills I need to learn to get up and running with full django/python?
The question can't easily be answered because you haven't described the app. You have to actually write down the technology stack -- in detail -- or you'll never know what skills you need.
The skill list mostly comes from your technology choices. So write down your technology choices. (That's part of configuration management, an important skill you'll need if you move away from GAE.)
Since you've chosen to talk about yourself and not your technology choices, I can only guess what technologies you're using and what skills you'll need.
Here's a common technology stack.
Technically, the OS doesn't matter. Most hosting environments use open source GNU/Linux because the licensing is inexpensive. You, too, can do this. You can start with VMWare and download a nice Linux distro. Or, you can buy a very cheap PC and install Linux directly from a DVD image that you can download and burn.
My company demands that I use the Windows PC they give me. So I develop in Windows and test in VMWare Linux (Fedora 14, actually)
To learn Linux, start with a download and install. Then find a tutorial. Then stop using Windows and learn by doing. Flipping back and forth between Windows and Linux is difficult. I can do it because I don't know Windows very well. I treat Windows as a hyper-complex IDE with all kinds of non-standard, non-POSIX quirks that I try to ignore.
RDBMS. Python comes with SQLite. For a lot of applications, it works fine. It works because web sites tend to be heavy on queries and light on updates/inserts, so SQLite works well. MySQL is nice. It's easy to install and runs on Windows as well as other OS's.
The good thing about Django is you need to know very little SQL. Very little.
However, you do need to know a tiny bit about the "Data Control Language" (Grant, Revoke and Create User) to work with MySQL. You won't create a lot of users. But you do need to create a few to get things running. Also, as your database matures, you'll often need to know a little bit about the "Data Definition Language" (Drop Table).
You will need to know how to backup and restore your database. That's absolutely critical.
So find Database Administrator tutorials to get started.
If your application really uses a lot of sophisticated data, you'll need to buy real books on database design so you can understand how the Django models really work. You don't need to become a SQL guru, but it does help to know what's really going on inside the database.
Application Server. We use Apache with the mod_wsgi module. There are numerous choices. Hosting services vary in what they require and what they permit. Some have Apache, mod_wsgi and Django pre-configured. Some don't. Some do not permit tinkering with the Apache configuration. Some do. You probably don't need to know much about this, because you can probably find a hosting service that will handle the details.
Apache tutorials are all over the place. mod_wsgi is very simple; once you understand how Apache works, mod_wsgi is obvious.
Since you have stuff working, presumably you know about HTML and CSS. Those are important skills, but you probably already have them.
Since you have stuff working, you also might know a lot about Configuration Management and how to control change. This isn't obvious and many people do it wrong. If you don't know about CM, you should find some books or articles on configuration management and change control.
Since you have stuff working, you also might know a lot about quality assurance, unit testing and related topics. If you don't have a complete suite of unit tests, you should probably start learning about unit testing before you start any serious coding for the next release of your product.
Bug Tracking, Problem Reporting, Feature Requests and other management skills are also essential. I can't tell if you have them or don't have them. Or what tools you're using for this. If you're working by yourself, you don't need a lot of formality. However, these are critical skills even if you're a one-person developer. Sticky-Notes on your workstation can work. What's important is the skills to manage bugs and features.
Hey Tom,
I suggest the reasonable evaluation you can make is carefully list the advantages and disadvantages of the choices.
The way I don't regret taking was physical rack server (2006-07), moved to virtual hosting (2008) and now moved to GAE (2009-current). Seeing the rate new features get added to GAE and the costeffectiveness are more reasons to stay. I agree more stuff django can are needed like in my case form preview and form validation with GAE are difficult or too difficult to set up.
I tried RoR and soon thought RoR requires more code to do the same GAE can with less code.
Also with GAE you have absolutely no hardware that can break. If you move to a rack server or a virtual hosting where there are places you can get 5 GB hosting for free but you don't have a plan when you run out of 5 GB and may need to migrate again which you don't want.
MySQL has been around for over 10 years and is quite a different kind of system. It's possible to save blobs in MySQL but don't you think the blobstore GAE has is much better?
If you choose to migrate to a solution with MySQL you can export you data from GAE and import it to MySQL with a tool such as approcket.
Kind regards/Niklas R
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This will not be a "programming" question but more technology / platform related question. I'm trying to figure out whether Python can be a suitable Java alternative for enterprise / web applications.
Which are the ideal cases where you would prefer to use Python instead of Java? How would a typical Python web application (databases/sessions/concurrency) perform as compared to a typical Java application? How do specific Python frameworks square up against Java based frameworks (Spring, SEAM, Grails etc.)?
For businesses, switching from the Java infrastructure to a Python infrastructure .. is it too hard/expensive/resource intensive/not viable? Also shed some light on the business case for providing a Python + Google AppEngine based solution to the end customer. Will it be cost effective in an typical scenario?
Sorry if I am asking too wide a question, I would have liked to keep it specific, but I need your help to evaluate Python as a whole from the perspectives of the programmers, service providing company and end business customer.
For an SME, a Python/GoogleAppEngine based technology stack is a clear scalable and affordable platform. But what about a large MNC that already has a lot invested in Java.
Thank you so much. I am researching this myself and will gladly share my conclusions here!
Thank you,
Srirangan
An enterprise that already has a terabucks of Java investments should add jython to their mix of technologies -- it can be adopted gradually and progressively, at first for ancillary functions such as testing, "one-off" data migrations &c, prototyping of new functionality, cases in which using some existing open source Python library is obviously very handy, and so on, and so forth -- then, as the many Java developers in the company learn to use Jython, some of the prototypes will just be put in production as Jython code because there would be no advantage recoding them, some old subsystem needing recoding will be recoded in Jython, and so forth.
It's never really a wise decision to throw away a huge existing and working codebase and the ginormous investment it represents -- Python's strengths include its wealth of strong, production-level implementations, how well they "play with others", and how well Python can gradually and incrementally infiltrate most any development shop.
The larger your investment in an existing technology is, the more expensive it is to move away from it. COBOL is perhaps the best example here.
That investment isn't just in porting existing solutions, but also in retraining or hiring new staff so that you have the skill sets to build and support the new technologies even while still maintaining your legacy solutions.
Add to that the fact that for most large Multinational Corporations, software isn't their core business. As long as it functions effectively and fulfills the business need, they don't tend to care so much about the 'details'.
You need to be able to offer some pretty compelling benefits to overcome this kind of inertia.
Sad but true.
If you need to do the sort of things you can do with Django, then Django and Python is totally what you want. Google App Engine runs Django as well. So, you can do a Django app and host it on Google App Engine, and later change your mind and switch to conventional server hosting, or self-hosting if you have your own server.
I haven't tried Google App Engine but my understanding is that the price is quite reasonable for what you get. Google's IT department does a great job of keeping their data centers going; if you outsource the hosting to Google App Engine you know your data is backed up, you know the servers won't go down, and even if a backhoe takes a whole Google data center off the Internet, some other Google data center will keep serving up your application to your customers. You also know that if your application suddenly becomes hugely popular, Google App Engine wil l scale up automatically to handle the load. (I think you set a cap for the maximum you are willing to pay, and it scales until it hits the cap. But as I said I haven't used it and I'm not certain.)
I haven't used Java yet, but from what I have seen of it, Python is a much more expressive language and skilled Python coders can get more work done in a day just because the language is that much better. However, if you already have invested in Java and have in-house expertise in Java, you would be crazy to walk away from that overnight. The correct thing is to pick one new project to just try out that crazy Python thing.
And I really do recommend Django. You can get the Django book and try out the tutorial. If your first pilot project in Python is a Django project, you should have an easy time of things.
The answer to your question is yes. Python can be well suited for Enterprise because python is a language which has raw power, flexible and can be glued with other programming languages. What enterprise really requires is a language which does everything and i feel python is already enterprise ready. If you want examples then i believe there can be no bigger example than google. Google is running python internally and externally for its business critical applications. The only problem with python is that it is not very well recognized by top MNC company and we as a python programmer find hard time convincing the management team. I guess you will face the same issue. But i guarantee you once you get your feet wet in python, you will understand its true power
There is -- almost -- no usable "Business Case" for any technology choice.
"what about a large MNC that already has a lot invested in Java" Ask around. See if there's a business case for Java.
I doubt you'll find anything. Most companies drift into technology choices slowly.
There was no business case for COBOL -- it was the only game in town in the olden days.
There is rarely a business case for Java. What usually happens is that some visionary individual started building the first web site (probably in Perl). The "web thing" gained traction, and some vision individual started building web sites in Java. Eventually, the success of those small teams indicated to others that Java had advantages over COBOL.
Managers say the words "make a business case", but watch what they actually do. They listen to (1) their peers, (2) successful people.
To make the "business case" for Python, you have to be that visionary individual.
1) Use Python.
2) Be successful.
3) Share your successes.
4) Be prepared to explain that your success is due to your tools, not your personal level of genius and charisma.
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Businessmen typically want a web application developed. They are aware of .net or J2EE by names, without much knowledge about either.
Altho' Rails and Django offer for a much better and faster development stack, it is a big task to convince businessmen to use these platforms.
The task begins with introducing Django (or Rails), quoting some blog/research. Then making a case for the use of the framework for the specific project.
Lot of the task is repetitive. What are the sources/blogs/whitepapers and other materials you use to make a case for django (or Rails)
Don't you think there should be a common brochure developed that many development agencies could use to make the same case, over and again. Are there any such ones, now?
There seems to be enough discussion on Django vs Rails. Whereas the need is (Django and Rails) vs (.net and J2EE), at least so, while making a business case. Both represent a faster pragmatic web development in a dynamic language.
It's easier to ask forgiveness than permission.
First, build the initial release in Django. Quickly. Build the model well (really well!). But use as much default admin functionality as you can.
Spend time only only reporting and display pages where the HTML might actually matter to the presentation.
Show this and they'll only want more. Once they've gotten addicted to fast turnaround and correct out-of-the box operation, you can discuss technology with them. By then it won't matter any more.
You need to speak the language of business: money.
"If we do it Rails, it will cost you 50% less than the same functionality in Java."
Your percentage may vary, and you might need to also include hosting and upkeep costs, to show how it balances out.
When you're convincing other programmers, sure, talk about development speed and automation of repetitive tasks. But talk bottom-line cost to a business person.
Before you begin making the case for Django or Rails, you have to be convinced it's the right stack first in the context of the business person's needs. If the business person is an entrepreneur, he may have other factors that go beyond how quickly can the solution be developed. For example:
If its an enterprise play that's being developed (something like SalesForce.com, SugarCRM, etc.) it may make sense to have it written in Java because this makes acquisitions and mergers easier with potential Java-based suitors.
If its an internal IT play for a custom solution in a large company, they may already have a significant amount MS infrastructure in place. It may not make sense to have your client install SQLServer or complicate their stack further with a Rails/Django friendly stack.
If you've cross this chasm and are convinced you have the client's best interest in mind, then I would look for examples on the Internet where the same application has been authored in both Java and Rails/Django. Here's an example of the Pet Store implemented in Rails.
http://www.anassina.com/projects/railspetstore/
You can download the source code and demonstrate to your client how much less code is needed to achieve the same result.
Explain to the client why less code is valuable: the less code you write, the fewer bugs you will have.
The first 2 arguments from the top of my mind:
Easier and faster development = cheaper product, less time to market.
SO optimization out of the box.
While many of you made some good suggestions, WRT the talks/resources for using these frameworks, you may also note to have a look at talk on redesigning yellow pages in ROR:
Summary from the site:
This talk explains how
YELLOWPAGES.COM, one of the
highest-traffic websites in the U.S.,
was written using Ruby on Rails, how
it was scaled to handle the traffic
and how the software architecture
evolved. Also: the reasons for
choosing Ruby on Rails.
The best case to be made for either of these frameworks is their ability to automate repetitive and time-consuming tasks. This allows developers to be faster and more productive which in turn means projects are delivered faster.
The problem with a "brochure" approach is that it doesn't address the clients needs. Putting the language/platform of choice into a presentation that addresses the clients goals is much more likely to sell them - both on the tools you want to use, as well as you as a provider. As long as you can show that your approach will solve the problem (preferably with the least amount of expense), you'll have fewer objections and less of the "but I've heard that xxx is the best".
I know it's kinda subjective but, if you were to put yourself in my shoes which would you invest the time in learning?
I want to write a web app which deals securely with relatively modest amounts of peoples private data, a few thousand records of a few Kb each but stuff that needs to be kept safe, addresses, phone numbers etc. I've done several web projects in PHP/MYSQL and have decided, handy though it is I really don't like PHP and don't want to do another large project in it...
As such I figure I'd best learn something new and so I am considering 2 options (although I'll happily entertain others if you have suggestions). I'm having terrible trouble deciding though. They both look quite involved so rather than just jump in and potentially waste days getting up to speed enough on both of them to make an informed choice I thought I'd come here and canvas some opinion.
So the two options I'm considering are...
One of the PYTHON Web frameworks - TurboGears seems well regarded?
Advantage: Of all the languages I ever tried Python is by far and away my favorite. There's loads of frameworks to choose from and I have done quite a lot of non web python coding over the last few years.
Disadvantage: There's loads to choose from so it's hard to pick! Need to run single server process? or mod_python? which I don't like the sound of. What I do like is the notion of process separation and compartmentalization, i.e. if one users account is compromised it gives an attacker no leverage against the rest of the system. I'm not clear to what extent a python solution would handle that.
Writing it as a SEASIDE app Which I guess runs on a squeak app server?
Adv: From what I've heard it would permit good compartmentalization of users as each would have their own little private VM independent of all the systems other users which sounds wonderful from a security, scaling and redundancy standpoint.
Dis: I've not done any Smalltalk since Uni 15 years back and I never dug too deep into it then. I don't see much entry level help for seaside or that many projects using it. I suspect setting a server up to run it is hard for the same reason i.e. not because it's inherently hard but just cause there will be less help online and a presumption you are already rather au fait with Sqeak/Smalltalk.
So, what do people think? Would I be able to efficiently get the kind of strong separation and compartmentalization I'm after with a Python framework? Is Seaside as good as I think in terms of insulating users from each other? Might I be better off, security wise, sticking to the languages I'm most familiar with so I don't make any n00b mistakes or will Seaside be worth worth scaling the learning curve and prove more secure, comprehensible and maintainable in the long run? At the end of the day it's not a life or death decision and I can always bail if I start with one and then hate it so pls nobody get all holy language war and start flaming anyone! ;-)
Cheers for any replies this gets,
Roger :)
Disclaimer: I really don't like PHP, Python is nice, but doesn't come close to Smalltalk in my book. But I am a biased Smalltalker. Some answers about Seaside/Squeak:
Q: Which I guess runs on a squeak app server?
Seaside runs in several different Smalltalks (VW, Gemstone, Squeak etc). The term "app server" is not really used in Smalltalk country. :)
Q: From what I've heard it would permit good compartmentalization of users as each would have their own little private VM independent of all the systems other users which sounds wonderful from a security, scaling and redundancy standpoint.
Yes, each user has its own WASession and all UI components the user sees are instances living on the server side in that session. So sharing of state between sessions is something you must do explicitly, typically through a db.
Q: I've not done any Smalltalk since Uni 15 years back and I never dug too deep into it then. I don't see much entry level help for seaside or that many projects using it.
Smalltalk is easy to get going with and there is a whole free online book on Seaside.
Q: I suspect setting a server up to run it is hard for the same reason i.e. not because it's inherently hard but just cause there will be less help online and a presumption you are already rather au fait with Sqeak/Smalltalk.
No, not hard. :) In fact, quite trivial. Tons of help - Seaside ml, IRC on freenode, etc.
Q: Is Seaside as good as I think in terms of insulating users from each other?
I would say so.
Q: Might I be better off, security wise, sticking to the languages I'm most familiar with so I don't make any n00b mistakes or will Seaside be worth worth scaling the learning curve and prove more secure, comprehensible and maintainable in the long run?
The killer argument in favor of Seaside IMHO is the true component model. It really, really makes it wonderful for complex UIs and maintenance. If you are afraid of learning "something different" (but then you wouldn't even consider it in the first place I guess) then I would warn you. But if you are not afraid then you will probably love it.
Also - Squeak (or VW) is a truly awesome development environment - debugging live Seaside sessions, changing code in the debugger and resuming etc etc. It rocks.
Forget about mod_python, there is WSGI.
I'd recommend Django. It runs on any WSGI server, there are a lot to choose from. There is mod_wsgi for Apache, wsgiref - reference implementation included in Python and many more. Also Google App Engine is WSGI, and includes Django.
Django is very popular and it's community is rapidly growing.
I'd say take a look at Django. It's a Python framework with a ready-made authentication system that's independent of the hosting OS, which means that compromises are limited to the app that was compromised (barring some exploit against the web server hosting the Python process).
I've been getting into seaside myself but in many ways it is very hard to get started, which has nothing to do with the smalltalk which can be picked up extremely quickly. The challenge is that you are really protected from writing html directly.
I find in most frameworks when you get stuck on how to do something there is always a work around of solving it by using the template. You may later discover that this solution causes problems with clarity down the road and there is in fact a better solutions built into the framework but you were able to move on from that problem until you learned the right way to do it.
Seaside doesn't have templates so you don't get that crutch. No problems have permanently stumped me but some have taken me longer to solve than I would have liked. The flip side of this is you end up learning the seaside methodology much quicker because you can't cheat.
If you decide to go the seaside route don't be afraid to post to the seaside mailing list at squeakfoundation.org. I found it intimidating at first because you don't see a lot of beginner questions there due to the low traffic but people are willing to help beginners there.
Also there are a handful of seaside developers who monitor stackoverflow regularly. Good luck.
Have you taken a look at www.nagare.org ?
A framework particularly for web apps rather than web sites.
It is based around the Seaside concepts but you program in Python (nagare deploys a distribution of python called Stackless Python to get the continuations working).
Like Seaside it will auto generate HTML, but additionally can use templates as required.
It has been recently open sourced by http://www.net-ng.com/ who themselves have many years experience in delivering web apps/sites in quality web frameworks like zope and plone.
I am researching it myself at the moment to see if it fits my needs, so can't tell you what I think of it in the wild. If you take a look, please give your feedback.
While considering a Smalltalk web framework, look at Aida/Web as well. Aida has built-in security with user/group/role management and strong access control, which can help you a lot in your case. That way you can achieve safe enough separation of users at the user level in one image. But if you really want, you can separate them with running many images as well. But this brings increased maintenance and I'd think twice if it is worth.
I'm toying with Seaside myself and found this tutorial to be invaluable in gaining insight into the capabilities of the framework.
I think you've pretty much summed up the pros and cons. Seaside isn't that hard to set up (I've installed it twice for various projects) but using it will definitely affect how you work--in addition to re-learning the language you'll probably have to adjust lots of assumptions about your work flow.
It also depends on two other factors
If other people will eventually be maintaining it, you'll have better luck finding python programmers
If you are doing a highly stateful site, Seaside is going to beat the pants off any other framework I've seen.
There is now an online book on Seaside to complete the tutorial pointed out earlier.