been defined the order in which the functions appear in the file ( the order in which they are createddoes not matter in the csv html py programthe first function we call is main(which in turn calls print_start(and then print_line(and print_line(calls extract_ fields(and escape_html(the program structure we have used is shown in figure import sys def main()def print_start()def print_line()calls def extract_fields()calls calls def escape_html()def print_end()main(figure the csv html py program' structure when python reads file it begins at the top so for this exampleit starts by performing the importthen it creates the main(functionand then it creates the other functions in the order in which they appear in the file when python finally reaches the call to main(at the end of the fileall the functions that main(will call (and all the functions that those functions will callnow exist execution as we normally think of it begins where the call to main(is made we will look at each function in turnstarting with main(def main()maxwidth print_start(count while truetryline input(if count = color "lightgreenelif count color "whiteelsecolor "lightyellow