def sector_area(r,a):
    
    pi=22/7
    if a >= 360:
        return None
    sectorarea = (pi*r**2) * (a/360)
    return sectorarea
def is_not_prime(n):
    import math
    
    result = False
    for i in range(2,int(math.sqrt(n)) + 1):
        if n % i == 0:
            result = True
    return result