Python Functional Programming (2)--return function

Python's functions can not only return data types such as int, str, list, dict, but also return functions!
Example One. summation [1, 2, 3, 4]
def calc_sum (LST):
Def calc_sum ():
return sum (LST)
Return calc_sum

f = Calc_sum ([1, 2, 3, 4])
Print (f ())
Example Two. Write a function Calc_prod (LST) that receives a list, returns a function, and returns a function that calculates the product of the parameter.
From Functools import reduce
def calc_prod (LST):
def prod ():
return reduce ((lambda A, b:a*b), LST)
Return PROD

f = Calc_prod ([1, 2, 3, 4])
Print (f ())

Python Functional Programming (2)--return function