fastest way to find the mean python code example

Example 1: how to calculate mean in python

import statistics

a = [1,2,3,4,5]

mean = statistics.mean(a) 
#Similar for other values such as variance, standard deviation

Example 2: calculate mean on python

def calculate_mean(n):
    s = sum(n)
    N = len(n)
    
    mean = s / N
    
    return mean