Lab 4x Hello Python - Calculate circumference and area of a circle from its diameter (function)

PI=3.14

def setup():
    cal_area(7)
    cal_circumference(7)

def cal_area(diameter):
    area_of_a_circle=PI*(diameter/2)*(diameter/2)
    print("Diameter is" ,diameter)
    print("Area of a circle is" ,area_of_a_circle)
    return area_of_a_circle
 
def cal_circumference(diameter):
    circumference=PI*diameter
    print("Circumference is" ,circumference)
    return circumference
 
setup()