this is an initial version of the book covering the following design patternsdp# model-view-controller pattern dp# command pattern dp# observer pattern dp# facade pattern dp# mediator pattern dp# factory pattern dp# proxy pattern because the current number of design patterns is handfulwe have not categorized them based on classifications mentioned earlier by the time we publish next version of this book with target of patternsthe content would be organized into classification-wise grouping of pre-requisites basic knowledge of object-oriented programming basic knowledge of python (see how would pareto learn python by rahul verma to get startedonline version an online version of the book is available on testing perspective website at the following linkthis version is more updated version of this ebook at any given point of time in terms of corrections and updated content we plan to release updated version of this offline pdf version at regular intervals to keep up with the updated content in online version feedback there would be mistakes some of them would be directly visible and some of them could be more subtle please write back to us so that we can correct the same you can use the contact form at testing perspective website to do so or write to us at feedback@testingperspective com www testingperspective com