first add files

lib/dbus/_compat.py

@@ -0,0 +1,15 @@
+# Python 2 / Python 3 compatibility helpers.
+# Copyright 2011 Barry Warsaw
+# Copyright 2021 Collabora Ltd.
+# SPDX-License-Identifier: MIT
+
+import sys
+
+is_py3 = True
+is_py2 = False
+
+if sys.version_info.major < 3:
+    raise AssertionError(
+        'Python 2 has reached end-of-life, and dbus-python no longer '
+        'supports it.'
+    )