What am I missing here?

Error text:

```
Oops, try again. It looks like the sum of grades was not printed! Make sure you are
printing it on its own line.
```

Here’s my code:

```
grades = [100, 100, 90, 40, 80, 100, 85, 70, 90, 65, 90, 85, 50.5]
def print_grades(grades):
for grade in grades:
print grade
def grades_sum(grades):
total = 0
for grade in grades:
total += grade
return total
def grades_average(grades):
sum_of_grades = grades_sum(grades)
average = sum_of_grades / float(len(grades))
return average
def grades_variance(grades)
average = grades_average(grades)
variance = 0
for grade in grades:
variance += (average-grade)**2
return variance/len(grades)
def grades_std_deviation(variance):
return variance**0.5
def print_grade_info(grades):
for grade in grades:
print grade
variance = grades_variance(grades)
print "Sum: "+str(grades_sum(grades))
print "Average grade: "+str(grades_average(grades))
print "Variance: "+str(grades_variance(grades))
print "STDDev: "+str(grades_std_deviation(variance))
print_grade_info(grades)
```

Output:

```
100
100
90
40
80
100
85
70
90
65
90
85
50.5
Sum: 1045.5
Average grade: 80.4230769231
Variance: 334.071005917
STDDev: 18.2776094147
```