input: def calculate_square_root(n: float) -> float:
      """Calculate the square root of a positive number.
      >>> calculate_square_root(100)
      10.0
      >>> calculate_square_root(81)
      9.0
      """
      import math
      return math.sqrt(n)
output:     if n < 0:
          raise ValueError("Cannot calculate square root of a negative number")