python' development cycle is dramatically shorter than that of traditional tools in pythonthere are no compile or link steps--python programs simply import modules at runtime and use the objects they contain because of thispython programs run immediately after changes are made and in cases where dynamic module reloading can be usedit' even possible to change and reload parts of running program without stopping it at all figure - shows python' impact on the development cycle figure - development cycles because python is interpretedthere' rapid turnaround after program changes and because python' parser is embedded in python-based systemsit' easy to modify programs at runtime for examplewe saw how gui programs developed with python allow developers to change the code that handles button press while the gui remains activethe effect of the code change may be observed immediately when the button is pressed again there' no need to stop and rebuild more generallythe entire development process in python is an exercise in rapid prototyping python lends itself to experimental and interactive program developmentand it encourages developing systems incrementally by testing components in isolation and putting them together later in factwe've seen that we can switch from testing components (unit teststo testing whole systems (integration testsarbitrarilyas illustrated in figure - but what about that bottleneck