这个python程序应该怎么写呢？

这是将一个表格中的成绩通过xlrd 打开将成绩一览输出，然后将里面的成绩进行比较，得出不同的等级，这些等级再形成一个列表，根据这些做出一个图

import xlrd
from matplotlib import pyplot as plt
#表格属性为姓名+语文+数学+英语+科学 对应这几个字段

class Score_level_map:
    scoreList = []
    levelList = []
    def __init__(self):
        self.file = xlrd.open_workbook("C:/Users/suoer/Desktop/1.xls")

    def getSource(self):
        table=self.file.sheets()[0]
        for i in range(table.nrows):
            if i!=0:
                data =table.row_values(i)
                self.scoreList.append(data)

    def getLevel(self):
        for i in self.scoreList:
            list = [i[0]]
            for s in i:
                if type(s)!=str:
                    if s>=90:
                        list.append("优秀")
                    elif 80<=s<=89:
                        list.append("良好")
                    elif 70<=s<=79:
                        list.append("中等")
                    elif 60<=s<=69:
                        list.append("及格")
                    elif s<60:
                        list.append("不及格")
            self.levelList.append(list)
        print(self.levelList)
    
    #只是一个学科的统计图
    def getShape(self):
        fig = plt.figure()
        labels = '优秀', '良好', '中等', '及格','不及格'
        sizes = []
        a=0
        b=0
        c=0
        d=0
        e=0
        for i in self.levelList:
            if i[1]=="优秀":
                a+=1
            elif i[1]=="良好":
                b+=1
            elif i[1]=="中等":
                c+=1
            elif i[1]=="及格":
                d+=1
            elif i[1]=="不及格":
                e+=1
        Sum=a+b+c+d+e
        sizes.append(a/Sum)
        sizes.append(b/Sum)
        sizes.append(c/Sum)
        sizes.append(d/Sum)
        sizes.append(e/Sum)
        explode = (0, 0, 0, 0, 0)  # only "explode" the 2nd slice (i.e. 'Hogs')

        fig1, (ax1, ax2) = plt.subplots(2)
        ax1.pie(sizes, labels=labels, autopct='%1.1f%%', shadow=True)
        ax1.axis('equal')
        ax2.pie(sizes, autopct='%1.1f%%', shadow=True, startangle=90, explode=explode,
                pctdistance=1.12)
        ax2.axis('equal')
        ax2.legend(labels=labels, loc='upper right')

        plt.show()


    def main(self):
        self.getSource()
        self.getLevel()
        self.getShape()

if __name__=="__main__":
    Score_level_map().main()