input: Write a function to prompt the user to enter the value of radius and calculate the area of a circle. If the user enters a negative value for the radius, the function should prompt the user to enter a positive value. The function should return the calculated area. The function should be named `calculate_circle_area`.
  
  assert calculate_circle_area() == 78.5
  assert calculate_circle_area() == 113.04
  
  def calculate_circle_area():
      Pi = 3.14
      while True:
          radius = float(input("Please enter the radius of the circle: "))
          if radius >= 0:
              break
          print("Radius cannot be negative. Please enter a positive value.")
      area = Pi * radius ** 2
      return area
output: def calculate_circle_area():
      Pi = 3.14
      while True:
          radius = float(input("Please enter the radius of the circle: "))
          if radius >= 0:
              break
          print("Radius cannot be negative. Please enter a positive value.")
      area = Pi * radius ** 2
      return area