#coding:utf-8
        # add an item to a set
        # remove an item from a set

        thisset = {"apple", "banana", "cherry"}
        thisset.add("orange")
        print(thisset)

        # add elements to a set
        thisset = {"apple", "banana", "cherry"}
        tropical = {"pineapple", "mango", "papaya"}
        thisset.update(tropical)
        print(thisset)

        #The object in the update() method does not have to be a set, 
        #it can be any iterable object (tuples, lists, dictionaries etc.).
        thisset = {"apple", "banana", "cherry"}
        mylist = ["kiwi", "orange"]
        thisset.update(mylist)
        print(thisset)

        thisset = {"apple", "banana", "cherry"}
        thisset.remove("banana")
        print(thisset)

        #If the item to remove does not exist, discard() will NOT raise an error.
        thisset.discard("cherry")
        print(thisset)

        thisset = {"apple", "banana", "cherry"}
        print(thisset)
        x = thisset.pop()
        print(x)
        print(thisset)

        thisset.clear()
        print(thisset)

        """
        thisset = {"apple", "banana", "cherry"}
        del thisset
        print(thisset)
        """