remove and add to set in python code example

Example 1: remove element form set in python

list1 = {1,2,3,4}
list1.remove(4)
print(list)
# {1,2,3}

Example 2: delete and return element from set python

>>> s = set([1])
>>> print s.pop()
1
>>> print s
set([])
>>> print s.pop()
KeyError: pop from an empty set