Solution 1

``````# Import the library here!
import math

# Area of Circle

Time for the `math` library. It has a lot of mathematical methods and numbers. Surprised?

Suppose you wanted to calculate the area of a circle with more precision and you didn't have pi memorized to 100 digits like most people do. You could either start learning about pi... or just use the `math` library!

Okay... time to make that hypothetical area of a circle program less hypothetical.

Create a function `area_of_circle` that receives the `radius` and returns the area of the circle (pi * r * r) using the `math` library to get your value for pi.

Examples:

``````area_of_circle(1) #  3.141592653589793

area_of_circle(2) # 12.566370614359172
``````

### Test Cases

test area radius three -

``````def test_area_radius_three():
assert area_of_circle(3) == 28.274333882308138``````

test area radius one -

``````def test_area_radius_one():
assert area_of_circle(1) == 3.141592653589793``````
# Import the library here! def area_of_circle(radius): pass