passing it list containing the program name (in this example'startfor windowsand the filename we also pass the shell=true keyword argumentwhich is needed only on windows the operating system knows all of the file associations and can figure out that it should launchsaynotepad exe to handle the hello txt file on macosthe open program is used for opening both document files and programs enter the following into the interactive shell if you have macsubprocess popen(['open''/applications/calculator app/']the calculator app should open projectsimple countdown program just like it' hard to find simple stopwatch applicationit can be hard to find simple countdown application let' write countdown program that plays an alarm at the end of the countdown at high levelhere' what your program will do count down from play sound file (alarm wavwhen the countdown reaches zero this means your code will need to do the following pause for second in between displaying each number in the countdown by calling time sleep(call subprocess popen(to open the sound file with the default application open new file editor tab and save it as countdown py step count down this program will require the time module for the time sleep(function and the subprocess module for the subprocess popen(function enter the following code and save the file as countdown py#python countdown py simple countdown script import timesubprocess timeleft while timeleft print(timeleftend='' time sleep(