Change Password

What will be the output of the following Python program?
z=set('abc')
z.add('san')
z.update(set(['p', 'q']))
z
{‘a’, ‘c’, ‘c’, ‘p’, ‘q’, ‘s’, ‘a’, ‘n’}
{‘abc’, ‘p’, ‘q’, ‘san’}
{‘a’, ‘b’, ‘c’, ‘p’, ‘q’, ‘san’}
{‘a’, ‘b’, ‘c’, [‘p’, ‘q’], ‘san}