<gh_stars>0
from Calculator.addition import addition
from Calculator.division import division
from Calculator.Square import square
from Calculator.Squareroot import squareroot
from Calculator.subtraction import subtraction
from Statistics.Mean import mean
from Statistics.PopulationVariance import variance


def psd(numbers):
    return squareroot(variance(numbers))

from Calculator.addition import addition
from Calculator.division import division
from Calculator.Square import square
from Calculator.Squareroot import squareroot
from Calculator.subtraction import subtraction
from Statistics.Mean import mean
from Statistics.PopulationVariance import variance


def psd(numbers):
    return squareroot(variance(numbers))