may be bit of pipe dream anyhow techniques like those outlined here may address slots and propertiesbut some attributes are entirely dynamicwith no physical basis at allthose computed on fetch by generic method such as __get attr__ are not data in the classic sense tools that attempt to display data in wildly dynamic language python must come with the caveat that some data is ethereal at bestwe'll also make minor extension to this section' code in the exercises at the end of this part of the bookto list superclass names in parentheses at the start of instance displaysso keep it filed for future reference for now to better understand the last of the preceding two pointswe need to wrap up this and move on to the next and last in this part of the book other design-related topics in this we've studied inheritancecompositiondelegationmultiple inheritancebound methodsand factories--all common patterns used to combine classes in python programs we've really only scratched the surface here in the design patterns domainthough elsewhere in this book you'll find coverage of other design-related topicssuch asabstract superclasses (decorators and type subclasses (static and class methods (managed attributes and metaclasses and for more details on design patternsthoughwe'll delegate to other resources on oop at large although patterns are important in oop work and are often more natural in python than other languagesthey are not specific to python itselfand subject that' often best acquired by experience summary in this we sampled common ways to use and combine classes to optimize their reusability and factoring benefits--what are usually considered design issues that are often independent of any particular programming language (though python can make them easier to implementwe studied delegation (wrapping objects in proxy classes)composition (controlling embedded objects)and inheritance (acquiring behavior from other classes)as well as some more esoteric concepts such as pseudoprivate attributesmultiple inheritancebound methodsand factories summary