Calculate Standard Deviation in Python

import math


def main():
	"""
	Calculates the standard deviation of a set of numbers.
	"""

	numbers = list(map(int, input("Enter numbers: ").split(",")))

	# Mean
	mean = sum(numbers) / len(numbers)

	# Variance
	variance = sum((num - mean) ** 2 for num in numbers) / len(numbers)

	# Standard Deviation
	standard_deviation = math.sqrt(variance)
	print(standard_deviation)


if __name__ == "__main__":
	main()