title: only the arrows keys works in pygame
body: <p>I am trying to use keyboard inputs on pygame.
  i figured out how to use the arrows keys with this code:</p>
  
  <pre><code>def events_handler():
      global right, left, up, down
      for event in pygame.event.get():
          if event.type == QUIT:
              pygame.quit()
              sys.exit()
          if event.type == KEYDOWN:
              if event.key == K_RIGHT:
                  right = True
              if event.key == K_LEFT:
                  left = True
              if event.key == K_UP:
                  up = True
              if event.key == K_DOWN:
                  down = True
              if event.key == K_RSHIFT:
                  plus = True
  
          if event.type == KEYUP:
              if event.key == K_RIGHT:
                  right = False
              if event.key == K_LEFT:
                  left = False
              if event.key == K_UP:
                  up = False
              if event.key == K_DOWN:
                  down = False
              if event.key == K_RSHIFT:
                  plus = False
  </code></pre>
  
  <p>and it work fine but a soon as i change the keys, it stop working. for example if i replace this:</p>
  
  <pre><code>        if event.type == KEYDOWN:
              if event.key == K_RIGHT:
                  right = True
        [...]
          if event.type == KEYUP:
              if event.key == K_RIGHT:
                  right = False
  </code></pre>
  
  <p>by this:</p>
  
  <pre><code>        if event.type == KEYDOWN:
              if event.key == K_d:
                  right = True
        [...]
          if event.type == KEYUP:
              if event.key == K_d:
                  right = False
  </code></pre>
  
  <p>i also tried others keys like <code>K_PLUS</code>, <code>K_LSHIFT</code> and sevral others but only the arrows keys seems to work.
  did someone know if this is normal and how to solve this issue ?</p>