code: def test_RGB(self):
      self.assert_pack("RGB", "RGB", 3, (1, 2, 3), (4, 5, 6), (7, 8, 9))
      self.assert_pack(
          "RGB",
          "RGBX",
          b"\x01\x02\x03\xff\x05\x06\x07\xff",
          (1, 2, 3),
          (5, 6, 7),
      )
      self.assert_pack(
          "RGB",
          "XRGB",
          b"\x00\x02\x03\x04\x00\x06\x07\x08",
          (2, 3, 4),
          (6, 7, 8),
      )
      self.assert_pack("RGB", "BGR", 3, (3, 2, 1), (6, 5, 4), (9, 8, 7))
      self.assert_pack(
          "RGB",
          "BGRX",
          b"\x01\x02\x03\x00\x05\x06\x07\x00",
          (3, 2, 1),
          (7, 6, 5),
      )
      self.assert_pack(
          "RGB",
          "XBGR",
          b"\x00\x02\x03\x04\x00\x06\x07\x08",
          (4, 3, 2),
          (8, 7, 6),
      )
      self.assert_pack(
          "RGB", "RGB;L", 3, (1, 4, 7), (2, 5, 8), (3, 6, 9)
      )
      self.assert_pack("RGB", "R", 1, (1, 9, 9), (2, 9, 9), (3, 9, 9))
      self.assert_pack("RGB", "G", 1, (9, 1, 9), (9, 2, 9), (9, 3, 9))
      self.assert_pack("RGB", "B", 1, (9, 9, 1), (9, 9, 2), (9, 9, 3))
  
imports: from __future__ import annotations
  import sys
  import pytest
  from PIL import Image
label_desc: Use image node_id 8 for calling the TestLibPack obj's underlying member method code with example usage: obj.test_RGB() without return types