input: 
  import math
  
  def calculate_square_root(number: float) -> float:
      """
      Calculate the square root of a given positive number.
      
      >>> calculate_square_root(100)
      10.0
      >>> calculate_square_root(16)
      4.0
      """
      return math.sqrt(number)
  
output:     if number < 0:
          raise ValueError("The number must be positive.")