text: 
  """
  Units for display sizes.
  """
  
  from typing import Tuple
  
  # Pixels according to the screen size measurement.
  ScreenUnit = int
  
  # x, y
  ScreenPosition = Tuple[ScreenUnit, ScreenUnit]
  SCREEN_POSITION_X = 0
  SCREEN_POSITION_Y = 1
  
  ZERO_SCREEN_POSITION: ScreenPosition = (0, 0,)
  
  # w, h
  ScreenSize = Tuple[ScreenUnit, ScreenUnit]
  SCREEN_SIZE_WIDTH = 0
  SCREEN_SIZE_HEIGHT = 1
  SCREEN_SIZE_W = SCREEN_SIZE_WIDTH
  SCREEN_SIZE_H = SCREEN_SIZE_HEIGHT
  
  ZERO_SCREEN_SIZE: ScreenSize = (0, 0,)
  
  # x, y, w, h
  ScreenArea = Tuple[ScreenUnit, ScreenUnit, ScreenUnit, ScreenUnit]
  SCREEN_AREA_X = 0
  SCREEN_AREA_Y = 1
  SCREEN_AREA_WIDTH = 2
  SCREEN_AREA_HEIGHT = 3
  SCREEN_AREA_W = SCREEN_AREA_WIDTH
  SCREEN_AREA_H = SCREEN_AREA_HEIGHT
  
  ZERO_SCREEN_AREA: ScreenArea = (0, 0, 0, 0,)
  
  # Quarter font unit.
  FontQUnit = int
  
  # For native screen dimensions...
  NativeScreenUnit = int
  
  # x, y
  NativeScreenPosition = Tuple[NativeScreenUnit, NativeScreenUnit]
  NATIVE_SCREEN_POSITION_X = 0
  NATIVE_SCREEN_POSITION_Y = 1
  
  # width, height
  NativeScreenSize = Tuple[NativeScreenUnit, NativeScreenUnit]
  NATIVE_SCREEN_SIZE_WIDTH = 0
  NATIVE_SCREEN_SIZE_HEIGHT = 1
  NATIVE_SCREEN_SIZE_W = NATIVE_SCREEN_SIZE_WIDTH
  NATIVE_SCREEN_SIZE_H = NATIVE_SCREEN_SIZE_HEIGHT
  
  # x, y, width, height
  NativeScreenArea = Tuple[NativeScreenUnit, NativeScreenUnit, NativeScreenUnit, NativeScreenUnit]
  NATIVE_SCREEN_AREA_X = 0
  NATIVE_SCREEN_AREA_Y = 1
  NATIVE_SCREEN_AREA_WIDTH = 2
  NATIVE_SCREEN_AREA_HEIGHT = 3
  NATIVE_SCREEN_AREA_W = NATIVE_SCREEN_AREA_WIDTH
  NATIVE_SCREEN_AREA_H = NATIVE_SCREEN_AREA_HEIGHT
  
  
  class ScreenRect:
      """Rectangle display on the screen."""
      __slots__ = ('__x', '__y', '__width', '__height', '__left', '__right', '__top', '__bottom',)
  
      def __init__(
              self,
              x: ScreenUnit, y: ScreenUnit, width: ScreenUnit, height: ScreenUnit,
              left: ScreenUnit, right: ScreenUnit, top: ScreenUnit, bottom: ScreenUnit
      ) -> None:
          self.__x = x
          self.__y = y
          self.__width = width
          self.__height = height
          self.__left = left
          self.__right = right
          self.__top = top
          self.__bottom = bottom
  
      @property
      def x(self) -> ScreenUnit:
          return self.__x
  
      @property
      def y(self) -> ScreenUnit:
          return self.__y
  
      @property
      def width(self) -> ScreenUnit:
          return self.__width
  
      @property
      def height(self) -> ScreenUnit:
          return self.__height
  
      @property
      def left(self) -> ScreenUnit:
          return self.__left
  
      @property
      def right(self) -> ScreenUnit:
          return self.__right
  
      @property
      def top(self) -> ScreenUnit:
          return self.__top
  
      @property
      def bottom(self) -> ScreenUnit:
          return self.__bottom
  
      def copy(self) -> 'ScreenRect':
          return ScreenRect(
              x=self.__x,
              y=self.__y,
              width=self.__width,
              height=self.__height,
              left=self.__left,
              right=self.__right,
              top=self.__top,
              bottom=self.__bottom
          )
      
      def get_area(self) -> ScreenArea:
          return self.__x, self.__y, self.__width, self.__height
  
      def __repr__(self) -> str:
          return 'ScreenRect(x={0}, y={1}, w={2}, h={3})'.format(
              self.__x, self.__y, self.__width, self.__height
          )
  
  
  EMPTY_SCREEN_RECT = ScreenRect(0, 0, 0, 0, 0, 0, 0, 0)
  