import csv
import math

with open('data.csv',newline='')as f:
    reader=csv.reader(f)
    fileData=list(reader)
data=fileData[0]
def mean(data):
    n=len(data)
    total=0
    for x in data:
        total+=int(x)
    mean = total/n
    return mean

squaredList=[]
for number in data:
    a=int(number)-mean(data)
    a=a**2
    squaredList.append(a)
sum=0
for i in squaredList:
    sum=sum+i
result=sum/(len(data)-1)
sd=math.sqrt(result)
print("Standard Deviation=> " + str(sd))
