code: def roundtrip(self, x, scaling=1):
      with NamedTemporaryFile(suffix=".png") as f:
          fname = f.name
  
      imsave(fname, x)
      y = imread(fname)
  
      assert_array_almost_equal((x * scaling).astype(np.int32), y)
  
file_path: scikit-image/skimage/io/tests/test_imread.py
imports: from tempfile import NamedTemporaryFile
  import numpy
  from skimage import io
  from skimage.io import imread, imsave, use_plugin, reset_plugins
  from skimage._shared import testing
  from skimage._shared.testing import TestCase, assert_array_equal, assert_array_almost_equal, fetch
  from pytest import importorskip
label_desc: Use image node_id 1 for calling the TestSave obj's underlying member method code with example usage: obj.roundtrip(x, scaling) without return types