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# This program computes the average grade you obtain in a class
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# 1. Input:
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grades = raw_input("Enter all your grades (separated with commas)-> ")
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# 2. Compute
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A = grades.split(",")
grades = map(float,A)
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S= sum(grades)
N = len(grades)
average = S/N
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# 3. Output result
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print "The average grade is : ",average