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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def empty_surface(fill_color, size=None):
 """Returns an empty surface filled with fill_color. :param fill_color: color to fill the surface with :type fill_color: pygame.Color :param size: the size of the new surface, if None its created to be the same size as the screen :type size: int-2-tuple """

    sr = pygame.display.get_surface().get_rect()
    surf = pygame.Surface(size or (sr.w, sr.h))
    surf.fill(fill_color)
    return surf