code: def test_str_special_method():
      codec = CompressedImageCodec("png", 80)
      assert str(codec) == "CompressedImageCodec('png', 80)"
  
file_path: petastorm/petastorm/tests/test_codec_compressed_image.py
imports: import io
  import numpy
  import pytest
  from PIL import Image
  from petastorm.codecs import CompressedImageCodec
  from petastorm.unischema import UnischemaField
label_desc: Use image node_id 8 for calling a global function with example usage: test_str_special_method() without return types