input: Write a python function to calculate the standard deviation of a list of numbers.
  assert calculate_std_deviation([2, 4, 4, 4, 5, 5, 7, 9]) == 2.0
  assert calculate_std_deviation([1, 2, 3, 4, 5]) == 1.4142135623730951
  assert calculate_std_deviation([10, 12, 23, 23, 16, 23, 21, 16]) == 4.898979485566356
output: import math
  
  def calculate_std_deviation(numbers):
      if not numbers:
          return 0.0
      mean = sum(numbers) / len(numbers)
      variance = sum((x - mean) ** 2 for x in numbers) / len(numbers)
      return math.sqrt(variance)