code: def line_step() -> Union[Tuple[int, int], Tuple[None, None]]:
      
      x = ffi.new("int *")
      y = ffi.new("int *")
      ret = lib.TCOD_line_step(x, y)
      if not ret:
          return x[0], y[0]
      return None, None
docs: After calling line_init returns (x, y) points of the line.
  
      Once all points are exhausted this function will return (None, None)
  
      Returns:
          Union[Tuple[int, int], Tuple[None, None]]:
              The next (x, y) point of the line setup by line_init,
              or (None, None) if there are no more points.
  
      .. deprecated:: 2.0
         Use `line_iter` instead.