pygame.draw.arc(screen, blue, [center[0] - 120, center[1] - 120, 240, 240], pi/2, pi/2+pi*i*koef, 15)
pygame.gfxdraw.aacircle(screen, center[0], center[1], 105, black)
pygame.gfxdraw.aacircle(screen, center[0], center[1], 120, black)

import pygame
from pygame.locals import *
import pygame.gfxdraw
import math

# Screen size
SCREEN_HEIGHT = 350
SCREEN_WIDTH = 500

# Colors
BLACK = (0, 0, 0)
WHITE = (255, 255, 255)
GREY = (150, 150, 150)
RED = (255,0,0)


 # initialisation
pygame.init()
screen = pygame.display.set_mode((SCREEN_WIDTH, SCREEN_HEIGHT))
done = False
clock = pygame.time.Clock()

# We need this if we want to be able to specify our
#  arc in degrees instead of radians
def degreesToRadians(deg):
    return deg/180.0 * math.pi

# Draw an arc that is a portion of a circle.
# We pass in screen and color,
# followed by a tuple (x,y) that is the center of the circle, and the radius.
# Next comes the start and ending angle on the "unit circle" (0 to 360)
#  of the circle we want to draw, and finally the thickness in pixels
def drawCircleArc(screen,color,center,radius,startDeg,endDeg,thickness):
    (x,y) = center
    rect = (x-radius,y-radius,radius*2,radius*2)
    startRad = degreesToRadians(startDeg)
    endRad = degreesToRadians(endDeg)

    pygame.draw.arc(screen,color,rect,startRad,endRad,thickness)


# fill screen with background
screen.fill(WHITE)
center = [150, 200]
pygame.gfxdraw.aacircle(screen, center[0], center[1], 105, BLACK)
pygame.gfxdraw.aacircle(screen, center[0], center[1], 120, BLACK)

pygame.display.update()

step = 10
maxdeg = 0

while not done:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            done = True

    maxdeg = maxdeg + step
    for i in range(min(0,maxdeg-30),maxdeg):
        drawCircleArc(screen,RED,(150,200),119,i+90,max(i+10,maxdeg)+90,14)
        #+90 will shift it from starting at the right to starting (roughly) at the top
    pygame.display.flip()

    clock.tick(2)  # ensures a maximum of 60 frames per second

pygame.quit()