Sort imports with isort

Keep imports alphabetically sorted and their order homogeneous across
Python source files.

The isort project has more feature and is more active than the
flake8-import-order plugin.

Most issues caught were simply import ordering from the same module.
Where imports were purposefully placed out of order, tag with
isort:skip.

1 files changed, 3 insertions, 5 deletions

diff --git a/tests/test_util_nodes.py b/tests/test_util_nodes.py
index 8fe9ee773..dd41022f3 100644
--- a/tests/test_util_nodes.py
+++ b/tests/test_util_nodes.py
@@ -11,15 +11,13 @@ from textwrap import dedent
 from typing import Any
 
 import pytest
-from docutils import frontend
-from docutils import nodes
+from docutils import frontend, nodes
 from docutils.parsers import rst
 from docutils.utils import new_document
 
 from sphinx.transforms import ApplySourceWorkaround
-from sphinx.util.nodes import (
-    NodeMatcher, extract_messages, clean_astext, make_id, split_explicit_title
-)
+from sphinx.util.nodes import (NodeMatcher, clean_astext, extract_messages, make_id,
+                               split_explicit_title)
 
 
 def _transform(doctree):