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Python Functional Python The Lambda Lambada Reduce

What is the correct use of map, add, reduce and product

Python IDE returns the in my opinion correct result of the requested challenge step which is a total of 978.63, right? Answer: Didn't find the correct use of reduce, map, add and product_sales. Why?

prices.py
from operator import add
from functools import reduce

prices = [
    (6.99, 5),
    (2.94, 15),
    (156.99, 2),
    (99.99, 4),
    (1.82, 102)
]

def product_sales(items):
    return items[0] * items[1]

total = reduce(add, (map(product_sales, prices)))

3 Answers

Okay found it. I used unneccessary paranthesis around the map statement for the add function.

Parsenz Dev
Parsenz Dev
13,198 Points

Take out the extra parentheses you've got around the map function. The last line should read:

total = reduce(add, map(product_sales, prices))

Thanks.