in the final section we saw how to create generic class to handle random access binary files that hold records of fixed sizeand then how to use the generic class in specific context this brings us to the end of all the fundamentals of python programming it is possible to stop reading right here and to write perfectly good python programs based on everything you have learned so far but it would be shame to stop now--python has so much more to offerfrom neat techniques that can shorten and simplify codeto some mind-bending advanced facilities that are at least nice to know abouteven if they are not often needed in the next we will go further with procedural and object-oriented programmingand we will also get taste of functional programming thenin the following we will focus more on broader programming techniques including threadingnetworkingdatabase programmingregular expressionsand gui (graphical user interfaceprogramming exercises ||the first exercise is to create simpler binary record file module than the one presented in this -one whose record size is exactly the same as what the user specifies the second exercise is to modify the bikestock module to use your new binary record file module the third exercise asks you to create program from scratch--the file handling is quite straightforwardbut some of the output formatting is rather challenging make newsimpler version of the binaryrecordfile module--one that does not use state byte for this version the record size specified by the user is the record size actually used new records must be added using new append(method that simply moves the file pointer to the end and writes the given record the __setitem__(method should only allow existing records to be replacedone easy way of doing this is to use the __seek_to_index(method with no state byte__getitem__(is reduced to mere three lines the __delitem__(method will need to be completely rewritten since it must move all the records up to fill the gapthis can be done in just over half dozen linesbut does require some thought the undelete(method must be removed since it is not supportedand the compact(and inplace_compact(methods must be removed because they are no longer needed all toldthe changes amount to fewer than new or changed lines and at least deleted lines compared with the originaland not counting doctests solution is provided in binaryrecordfile_ans py once you are confident that your simpler binaryrecordfile class workscopy the bikestock py file and modify it to work with your binaryrecordfile