code: def test_rotate_90(mode):
      im = HOPPER[mode]
      out = im.transpose(Transpose.ROTATE_90)
      assert out.mode == mode
      assert out.size == im.size[::-1]
  
      x, y = im.size
      assert im.getpixel((1, 1)) == out.getpixel((1, x - 2))
      assert im.getpixel((x - 2, 1)) == out.getpixel((1, 1))
      assert im.getpixel((1, y - 2)) == out.getpixel((y - 2, x - 2))
      assert im.getpixel((x - 2, y - 2)) == out.getpixel((y - 2, 1))
  
file_path: pillow/Tests/test_image_transpose.py
imports: from __future__ import annotations
  import pytest
  from PIL.Image import Transpose
  from .None import helper
  from .helper import assert_image_equal
label_desc: Use image node_id 3 for calling a global function with example usage: test_rotate_90(mode) without return types