nums = [1, 2, 3]
result = list(map(lambda x: x * 2, nums))
print(result)

nums = [0, 1, 2, 3, 4]
evens = list(filter(lambda x: x % 2 == 0, nums))
print(evens)

from functools import reduce
nums = [1, 2, 3, 4]
result = reduce(lambda x, y: x + y, nums)
print(result)

from collections import defaultdict

d = defaultdict(lambda: "default")
d["x"] = 42
print(d["x"], d["y"])