import Assignment1 while True: print("\n\n\n1.Access Character \n2.Concate String \n3.Find Substring \n4.Replace Substring \n0. Exit") n = int(input("Enter your choice: ")) if n==1: Assignment1.access_char() elif n==2: Assignment1.concate() elif n==3: Assignment1.sub_string() elif n==4: Assignment1.replace_substr() elif n==0: break else: print("You've entered wrong choice!")