input: Write a function that prompts the user to enter the value of radius to calculate the area of a circle. If the radius is valid, calculate the area and print it; otherwise, print an error message.
  assert calculate_circle_area()==None
  assert calculate_circle_area()==None
  assert calculate_circle_area()==None
  assert calculate_circle_area()==None
  assert calculate_circle_area()==None
output: def calculate_circle_area():
      try:
          radius = float(input("Enter the radius of the circle: "))
          if radius > 0:
              area = 3.14159 * radius * radius
              print(f"The area of the circle is {area}")
          else:
              print("Error: Radius must be positive.")
      except ValueError:
          print("Error: Invalid input. Please enter a valid number.")