Grocery 1.2

import sys
class grocery:
    a=[]#To store Name of Items
    b=[]#To store rate of corresponding Items
    bill=0
    serial=0
    choice=0#Use this in further Input
    def order(self):
        print("Name of Item:")
        nome = input()
        self.a.append(nome)#Append the item name to the list
        print("Rate of Item:")
        rate = int(input())
        self.b.append(rate)#Append the rate of the same item to list

    def display(self):
        series=0
        if self.a == []:
            print("Your Bucket List is empty! Insert Item")
        else:
            for i in range(0, len(self.a)):
                series+=1
                print("{}. {},{}/-".format(series,self.a[i], self.b[i]))

    def billl(self):
        self.bill= 0 # Again Re-Initializing bill to 0
        for i in self.b:
            self.bill += i #adding up all the rate from List b
        print("\t\tYour Bill is :", self.bill, "/-")

    def remove(self):
        if self.a == []:
            print("Your Bucket List is empty! Insert Item")
        else:
            self.serial = int(input("Enter Serial Number of Item to remove:"))
            if self.serial > len(self.a):
                print("Out of Range Try again")
            else:
                self.serial=self.serial-1
                self.a.remove(self.a[self.serial])
                self.b.remove(self.b[self.serial])
                print("List Updated")

    def edit(self):
        self.serial=int(input("Enter Serial Number of Item to edit:"))
        if self.serial>len(self.a):
            print("Out of Range Try again")
        else:
            self.serial=self.serial-1
            print("What do u want to change? \n1.Name\n2.Rate\n3.Both")
            bol=int(input())
            if bol==1:
                self.a.remove(self.a[self.serial])
                new_nome=input("Enter New name for it:")
                self.a.insert(self.serial,new_nome)
                print("List Updated")


            elif bol==2:
                self.b.remove(self.b[self.serial])
                new_rate = int(input("Enter New rate to it:"))
                self.b.insert(self.serial,new_rate)
                print("Rate Updated")

            elif bol==3:
                self.a.remove(self.a[self.serial])
                new_nome = input("Enter New name for it:")
                self.a.insert(self.serial, new_nome)
                print("Name Updated")
                self.b.remove(self.b[self.serial])
                new_rate=int(input("Enter New rate to it:"))
                self.b.insert(self.serial,new_rate)
                print("Rate Updated")


    def input(self):
        while self.choice!=6:
            print("\n\n1.Insert Grocery\n2.Display Bucket List\n3.Total Bill\n4.Remove item\n5.Edit Item\n6.Exit")
            self.choice=int(input("\nEnter Choice:"))
            if self.choice==1:
                self.order() #Calling all the functions

            elif self.choice==2:
                self.display()

            elif self.choice==3:
                self.billl()

            elif self.choice==4:
                self.remove()

            elif self.choice==5:
                self.edit()

            elif self.choice==6:
                print("Program Terminated")
                sys.exit()
            else:
                print("Try Again")

obj=grocery()
obj.input()