find the area of a regular polygon inscribed in a circle in python

main.py
import math

def area_of_inscribed_regular_polygon(n, r):
    """
    n: number of sides of the regular polygon
    r: radius of the circle
    returns: area of the regular polygon
    """
    # calculate the side length of the regular polygon
    s = 2 * r * math.sin(math.pi / n)
    
    # calculate the apothem of the regular polygon
    a = r * math.cos(math.pi / n)
    
    # calculate the area of the regular polygon
    A = 0.5 * n * s * a
    
    return A
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main.py
>>> area_of_inscribed_regular_polygon(6, 5)
64.9519052838329
>>> area_of_inscribed_regular_polygon(8, 10)
309.0169943749474
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