How to emulate sum() using a list comprehension?

Question

Is it possible to emulate something like sum() using list comprehension ?

For example - I need to calculate the product of all elements in a list :

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Answer 1

Starting Python 3.8, and the introduction of assignment expressions (PEP 572) (:= operator), we can use and increment a variable within a list comprehension and thus reduce a list to the sum of its elements:

total = 0
[total := total + x for x in [1, 2, 3, 4, 5]]
# 15

This:

• Initializes a variable total to 0
• For each item, total is incremented by the current looped item (total := total + x) via an assignment expression