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Python Functional Python The Lambda Lambada Reduce

reduce , map and add error

Finally, we're ready to find our totals. Create a variable named total. Use map() to find the per-product totals for each item in prices, then use reduce (and add) to find the total value.

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(item):
  return item[0] * item[1]


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

1 Answer

Steven Parker
Steven Parker
218,813 Points

I'm not sure why, but that space between add and the comma seems to upset the challenge checker.

:point_right: Just remove that space.

You also have a stray call to add on the line above (but the checker seems to ignore that).

:information_source: You might want to report this funny space issue to Treehouse Support. It may get you an Exterminator badge.

Kenneth Love
Kenneth Love
Treehouse Guest Teacher

Yep, I was being too picky.

It's best to avoid spaces like that, but they shouldn't make you fail.