frameworks on the client such as flexsilverlightand pyjamas (generally known today as rich internet applicationsriasculture shift asidethe examples formerly presented in this category were by themselves also insufficient to either teach or do justice to the subject tools rather than including incomplete (and nearly uselesscoverage of tools that are prone to both evolution and demise during this edition' expected lifespani now provide only brief overviews of the current hot topics in the web domainand encourage readers to search the web for more details more to the pointthe goal of the book you're reading is to impart the sort of in-depth knowledge of internet and web fundamentals that will allow you to use more advanced systems wellwhen you're ready to take the leap one exception herethe xml material of this prior was spared and relocated in expanded form to the text processing (where it probably belonged all alongin related veinthe coverage of zope' zodb object-oriented database was retainedalthough it was shortened radically to allow new coverage of orms such as sqlobject and sqlalchemy (againin overview formuse of tools available for today at this writingpython is still in its adoption phaseand some of the third-party tools that this book formerly employed in its examples are still available in python form only to work around this temporary fluxi've changed some code to use alternatives that already support today the most notable of these is the sql database section--this now uses the inprocess sqlite librarywhich is standard part of python and already in formrather than the enterprise-level mysql interface which is still at today luckilythe python portable database api allows scripts to work largely the same on bothso this is minor pragmatic sacrifice of special notethe pil extension used to display jpegs in the gui part was ported to just when it was needed for this updatethanks to fredrik lundh it' still not officially released in form as submit the final draft of this book in july but it should be soonand patches are provided in the book examples package as temporary measure advanced core language topics are not covered here more advanced python language tools such as descriptorspropertiesdecoratorsmetaclassesand unicode text processing basics are all part of the core python language because of thatthey are covered in the fourth edition of learning pythonnot here for exampleunicode text and the changes it implies for filesfilenamessocketsand much more are discussed as encountered herebut the fundamentals of unicode itself are not presented in complete depth some of the topics in this category are arguably application-level related too (or at least of interest to tool builders and api developers in general)but their coverage in learning preface xxix