code: def test_connection(self):
      source = pyvips.Source.new_from_file(JPEG_FILE)
      image = pyvips.Image.new_from_source(
          source, "", access="sequential"
      )
      filename = temp_filename(self.tempdir, ".png")
      target = pyvips.Target.new_to_file(filename)
      image.write_to_target(target, ".png")
  
      image = pyvips.Image.new_from_file(JPEG_FILE, access="sequential")
      image2 = pyvips.Image.new_from_file(filename, access="sequential")
  
      assert (image - image2).abs().max() < 10
  
file_path: pyvips/tests/test_connections.py
imports: import tempfile
  import pytest
  import pyvips
  from helpers import JPEG_FILE, WEBP_FILE, temp_filename, skip_if_no
label_desc: Use image node_id 2 for calling the TestConnections obj's underlying member method code with example usage: obj.test_connection() without return types