my code

grades = [100, 100, 90, 40, 80, 100, 85, 70, 90, 65, 90, 85, 50.5]

def print_grades(grades_input):

for grade in grades_input:

print grade

def grades_sum(scores):

total = 0

for score in scores:

total += score

return total

def grades_average(grades_input):

sum_of_grades = grades_sum(grades_input)

average = sum_of_grades / float(len(grades_input))

return average

def grades_variance(scores):

avg = grades_average(scores)

variance = 0

for score in scores:

variance += (score - avg) ** 2

return variance / len(scores)

variance = grades_variance(grades)

print variance

def grades_std_deviation(variance):

return variance ** 0.5

print grades_std_deviation(variance)

print print_grades(grades)

print grades_sum(grades)

print grades_average(grades)

print grades_variance(scores)

print grades_std_deviation(variance)

the error

Traceback (most recent call last):

File “python”, line 39, in

NameError: name ‘score’ is not defined