list1 = [1, 2, 3, 4, 5, 6]
list2 = [11, 12, 13, 14, 15, 16]
list3 = [21, 22, 23, 24, 25, 26]

lists = [list1, list2, list3]

for one_list in lists:
  one_list = filter(lambda el: el % 2 == 0, one_list)
print(lists)