Python Function Circle Area

# Python Function Area of Circle

# Define the function to find area of circle

def area_of_circle(radius):
    if radius < 0:
        print('Error: radius must be non-negative')
        return
    area = 3.14159 * radius**2
    return area

# input radius

radius = float(input('Enter radius of circle: '))

# call the function passing radius as argument

area = area_of_circle(radius)

# print answer that is area of circle

print('area of circle is: ', area)