ReportCard,py

def makeint(varname):
    try:
        int(varname)
        return True
    except ValueError:
        return False


def report_card():
    classname=[]
    grade=[]
    n=1
    subjectnum=raw_input('How many classes did you take? : ')
    while makeint(subjectnum) !=True :
        subjectnum=raw_input('Pls insert a valid numer : ')
    else:
        subjectnum2=int(subjectnum)
        while subjectnum2 > 0 :
            subjectname = raw_input('What is the name for class'+ str(n) +'? : ')
            classname.append(subjectname)
            subjectgrade=raw_input('What is  your grade for this class? : ')
            while makeint(subjectgrade) != True :
                subjectgrade=raw_input('Pls insert a valid numer : ')
            else:
                grade.append(subjectgrade)
                n += 1
                subjectnum2 -= 1
        else:
            pass
    witch = len(classname)
    while witch > 0:
        print str(classname[len(classname)-witch]) + " -- " + str(grade[len(grade)-witch])
        witch -= 1
    else:
        totalgrade=map(int,grade)
        print "Overall GPA : " + str(float(sum(totalgrade))/float(len(totalgrade)))

report_card()