To add, the if expression at the end of the list comprehension (behind the iterable / element emitter) is a filter predicate, determining whether an iterated / emitted element will take part in the comprehension. That means, it has to be boolean expression. if num != 11 else 22 is not a boolean expression, hence it is not suitable as a predicate to determine whether an element partakes in list comprehension...

Unfortunately, the (official) Python doc is rather vague and unspecific in documenting/explaining this... :-(

Self-deprecating pedantry: Realizing the nature of the predicate, technically else clauses can appear directly in the predicate expression -- albeit in a colossally stupid and useless way, for example by translating the boolean expression num != 11 into the equivalent form True if num != 11 else False, turning the list comprehension into the hilarious wonder that is [num for num in hand if (True if num != 11 else False)]. Yes, it's still not in the way the author of the Q actually intended to utilize else, but I am nevertheless going to claim "Mission accomplished" and pat myself on my shoulder now for the next 5 minutes... ;-P (;_;)

elgonzo‭ To add a little bit more pedantry, the filter predicate doesn't have to be exactly a boolean, because in Python any object can be tested for truth value. Which means I can do this:

values = ['abc', '', [], ['123'], 10, 0, range(0), range(1, 2)]
# "if s" checks if "s" is a truthy value
print([ s for s in values if s ])

And this will print ['abc', ['123'], 10, range(1, 2)].

Anyway, that's beside the point of the question (using else in list comprehension).