Use the builtin nullcontext

ASIM-5273

src/qmxgraph/api.py

@@ -1,7 +1,7 @@
-import sys
 import textwrap
 import weakref
 from contextlib import contextmanager
+from contextlib import nullcontext
 from typing import Any
 from typing import Generator
 from typing import List
@@ -1020,13 +1020,3 @@ def handle_message(msg_type, context, message):
         yield messages
     finally:
         qInstallMessageHandler(previous_handler)
-
-
-if sys.version_info[:] < (3, 7):
-
-    @contextmanager
-    def nullcontext(enter_result=None):
-        yield enter_result
-
-else:
-    from contextlib import nullcontext

tests/test_qt_js_integration.py

@@ -1,11 +1,11 @@
 import json
 import re
 import textwrap
+from contextlib import nullcontext
 from functools import partial
 
 import pytest
 import pytestqt.exceptions
-from _pytest.compat import nullcontext
 from PyQt5.QtCore import QByteArray
 from PyQt5.QtCore import QDataStream
 from PyQt5.QtCore import QIODevice