# average7.py def main(): fileName = input("What file are the numbers in? ") infile = open(fileName,'r') sum = 0.0 count = 0 line = infile.readline() while line != "": # update sum and count for values in line for xStr in line.split(","): sum = sum + eval(xStr) count = count + 1 line = infile.readline() print(" The average of the numbers is", sum / count) main()

Test all file average7.py .

3. With a single .txt file, revise file with line-by-line explanation. (Using # to add comment/explanation).

One file with line-by-line explanation, followed by one running result with IDLE shell information (try to use the same testing inputs to see the differences between each .py files).