Using the break statement to avoid repeating code in the class-average program. : for « Statement « Python Tutorial

# initialization phase
total = 0          # sum of grades
gradeCounter = 0   # number of grades entered

while 1:
   grade = raw_input( "Enter grade, -1 to end: " )   
   grade = int( grade )

   # exit loop if user inputs -1
   if grade == -1:
      break

   total += grade
   gradeCounter += 1
   
# termination phase
if gradeCounter != 0:
   average = float( total ) / gradeCounter
   print "Class average is", average
else:
   print "No grades were entered"

3.3.for
	3.3.1.	for Loops
	3.3.2.	break from for loop
	3.3.3.	Iterating List with for Loops
	3.3.4.	Iterating Through a Dictionary
	3.3.5.	for Loop and the range() Built-in Function
	3.3.6.	Counter-controlled repetition with the for structure and range function.
	3.3.7.	Summation with for.
	3.3.8.	Nested for loops
	3.3.9.	Calculating compound interest.
	3.3.10.	Using the break statement in a for structure.
	3.3.11.	Using the break statement to avoid repeating code in the class-average program.
	3.3.12.	Using the continue statement in a for/in structure.