average_mean.py

from __future__ import annotations


def mean(nums: list) -> float:
 """
 Find mean of a list of numbers.
 Wiki: https://en.wikipedia.org/wiki/Mean

 >>> mean([3, 6, 9, 12, 15, 18, 21])
 12.0
 >>> mean([5, 10, 15, 20, 25, 30, 35])
 20.0
 >>> mean([1, 2, 3, 4, 5, 6, 7, 8])
 4.5
 >>> mean([])
 Traceback (most recent call last):
 ...
 ValueError: List is empty
 """
 if not nums:
 raise ValueError("List is empty")
 return sum(nums) / len(nums)


if __name__ == "__main__":
 import doctest

 doctest.testmod()