Even values from lists into a set

Here is the given assignment + code:

Write a function even_value_set(list1, list2, list3), which receives
three lists containing integer items as arguments. The function
creates and returns a set that contains all items with even value from
all three lists.

def test():
    l = [[],[],[]]
    
    for i in range(3):
        for j in range(random.randint(7,14)):
            l[i].append(random.randint(1,35))
        print ("List" + str(i + 1) +":",l[i])
        
    print ("")
    s = even_value_set(l[0],l[1],l[2])
    print ("Return type:", str(type(s)).replace("<","").replace(">",""))
    print ("Set with even values only:", end = "")
    print (set(sorted(list(s))))
    
test()

import random

I tried using .union() and making adding lists into another before turning them into sets, but didn’t have any luck.

>Solution :

You can do this in a simply pythonic way. This function can be written as a simple oneliner using comprehension

def even_value_set(list1, list2, list3):
    return set([num for num in list1+list2+list3 if num % 2 == 0])

Basically, what we did here is concatenated all lists, fitered even numbers and then made it into a set.