in PYTHON

If varible counter contains an integer, then write an augmented assignment operation to decrement it by 1. A count-controlled for loop using the xrange function to average the scores for a class is given below and in the file PartD_average_with_for.py:

# Calculates the average score using a counter-controlled for-loop numberOfScores = input("Enter the number of scores to average: ")

total = 0.0;

for counter in xrange(numberOfScores):

score = input("Enter score #" + str(counter+1) + ": ") total = total + score

if numberOfScores > 0:

print "The average score is", total / numberOfScores