TST: Use IOError for Python 2 support.

Author: arokem

nibabel/loadsave.py

@@ -36,7 +36,7 @@ def load(filename, **kwargs):
        Image of guessed type
     '''
     if not op.exists(filename):
-        raise FileNotFoundError("No such file: '%s'" % filename)
+        raise IOError("No such file: '%s'" % filename)
     sniff = None
     for image_klass in all_image_classes:
         is_valid, sniff = image_klass.path_maybe_image(filename, sniff)

nibabel/tests/test_loadsave.py

@@ -54,7 +54,7 @@ def test_read_img_data():
 
 
 def test_file_not_found():
-    assert_raises(FileNotFoundError, load, 'does_not_exist.nii.gz')
+    assert_raises(IOError, load, 'does_not_exist.nii.gz')
 
 
 def test_read_img_data_nifti():