How to remove specific element from sets inside a list using list comprehension

Question

I think this may be related to set being mutable.

Basically, I can remove an element from a set using set.discard(element). However, set.d

Answer 1

>>> s = set( ['a' , 'b', 'c' , 'd' ] )
>>> print(s)
set(['a', 'c', 'b', 'd'])
>>>
>>> s -= {'c'}
>>> print(s)
set(['a', 'b', 'd'])
>>>
>>> s -= {'a'}
>>> print(s)
set(['b', 'd'])