#circle.py
#circumference and area of a circle

# The math "module" must be imported (its stuff made available)
import math   # math.pi

radius = float(input("Enter the radius of a circle: "))
  
circumference = 2 * math.pi * radius
area = math.pi * radius**2

print("Circumference =", circumference)
print("Area =", area)

print("math.pi:",math.pi)

# comment out import statement to see error.