TypeError:'module'对象不可调用我不明白为什么会这样,请帮助我不确定当我从超类调用时它没有读取子类它说它没有被调用
import RetailItem
import CashRegister
def main():
    #info1 = ['Jacket', '12', '59.95']
    #info2 = ['Designer', '40', '34.95']
    #info3 = ['Shirt', '20', '24.95']
    print ('there are three items')
    info1 = str(input('whats the description'))
    info2 = str(input('whats the units'))
    info3 = str(input('whats the price'))
    info4 = str(input('whats the description'))
    info5 = str(input('whats the units'))
    info6 = str(input('whats the price'))
    info7 = str(input('whats the description'))
    info8 = str(input('whats the units'))
    info9 = str(input('whats the price'))
    first = CashRegister.RetailItem(info1,info2,info3)
    second = CashRegister.RetailItem(info4,info5,info6)
    third = CashRegister.RetailItem(info7,info8,info9)
    #first1 = CashRegister.CashRegister(info1[0],info1[1],info1[2])
    print ("Description       Units in Inventory          Price\n")
    #print(first.show_items())
    print (first.__str__())
    print (second.__str__())
    print (third.__str__())
#main function