Lambda functions are small anonymous functions defined with the lambda keyword. They can have any number of arguments but only one expression.
square = lambda x: x ** 2
print(square(5)) # Output: 25
map(), filter(), and reduce()map(): Apply a function to all items in an input list.
nums = [1, 2, 3, 4, 5]
squares = list(map(lambda x: x ** 2, nums))
print(squares) # Output: [1, 4, 9, 16, 25]
filter(): Filter items in an input list.
evens = list(filter(lambda x: x % 2 == 0, nums))
print(evens) # Output: [2, 4]
reduce(): Apply a rolling computation to sequential pairs of values in a list.
from functools import reduce
product = reduce(lambda x, y: x * y, nums)
print(product) # Output: 120