text: 
  class Keys(object):
      """
      Set of special keys codes.
      """
  
      NULL = u'\ue000'
      CANCEL = u'\ue001'  # ^break
      HELP = u'\ue002'
      BACKSPACE = u'\ue003'
      BACK_SPACE = BACKSPACE
      TAB = u'\ue004'
      CLEAR = u'\ue005'
      RETURN = u'\ue006'
      ENTER = u'\ue007'
      SHIFT = u'\ue008'
      LEFT_SHIFT = SHIFT
      CONTROL = u'\ue009'
      LEFT_CONTROL = CONTROL
      ALT = u'\ue00a'
      LEFT_ALT = ALT
      PAUSE = u'\ue00b'
      ESCAPE = u'\ue00c'
      SPACE = u'\ue00d'
      PAGE_UP = u'\ue00e'
      PAGE_DOWN = u'\ue00f'
      END = u'\ue010'
      HOME = u'\ue011'
      LEFT = u'\ue012'
      ARROW_LEFT = LEFT
      UP = u'\ue013'
      ARROW_UP = UP
      RIGHT = u'\ue014'
      ARROW_RIGHT = RIGHT
      DOWN = u'\ue015'
      ARROW_DOWN = DOWN
      INSERT = u'\ue016'
      DELETE = u'\ue017'
      SEMICOLON = u'\ue018'
      EQUALS = u'\ue019'
  
      NUMPAD0 = u'\ue01a'  # number pad keys
      NUMPAD1 = u'\ue01b'
      NUMPAD2 = u'\ue01c'
      NUMPAD3 = u'\ue01d'
      NUMPAD4 = u'\ue01e'
      NUMPAD5 = u'\ue01f'
      NUMPAD6 = u'\ue020'
      NUMPAD7 = u'\ue021'
      NUMPAD8 = u'\ue022'
      NUMPAD9 = u'\ue023'
      MULTIPLY = u'\ue024'
      ADD = u'\ue025'
      SEPARATOR = u'\ue026'
      SUBTRACT = u'\ue027'
      DECIMAL = u'\ue028'
      DIVIDE = u'\ue029'
  
      F1 = u'\ue031'  # function  keys
      F2 = u'\ue032'
      F3 = u'\ue033'
      F4 = u'\ue034'
      F5 = u'\ue035'
      F6 = u'\ue036'
      F7 = u'\ue037'
      F8 = u'\ue038'
      F9 = u'\ue039'
      F10 = u'\ue03a'
      F11 = u'\ue03b'
      F12 = u'\ue03c'
  
      META = u'\ue03d'
      COMMAND = u'\ue03d'
  