title: pygame rotating a line
body: <p>I am trying to create a "radar" in Pygame. I am having trouble rotating the needle of the radar. How do I rotate it?</p>
  
  <pre><code>import pygame
  from pygame.locals import *
  SIZE = 800, 800
  pygame.init()
  screen = pygame.display.set_mode(SIZE)
  FPSCLOCK = pygame.time.Clock()
  done = False
  screen.fill((0, 0, 0))
  degree=0
  while not done:
      for e in pygame.event.get():
          if e.type == QUIT or (e.type == KEYDOWN and e.key == K_ESCAPE):
              done = True
              break
      for x in range(1,400,10):
          pygame.draw.circle(screen,(255,255,255),(400,400),x,1)
      line = pygame.draw.line(screen,(10,100,10),(400,400),(400,0),3)
      pygame.transform.rotate(line,degree)
          pygame.display.flip()   
          degree+=5
          FPSCLOCK.tick(40)
  </code></pre>