Support and test Python 3.10

Change-Id: I0dfbabc870017f6813884be6d4f6c6723a3a527b
diff --git a/setup.py b/setup.py
index 97d2b59..0fde749 100644
--- a/setup.py
+++ b/setup.py
@@ -19,6 +19,7 @@
         'Programming Language :: Python :: 3.7',
         'Programming Language :: Python :: 3.8',
         'Programming Language :: Python :: 3.9',
+        'Programming Language :: Python :: 3.10',
         'License :: OSI Approved :: BSD License',
         'Operating System :: OS Independent',
         'Intended Audience :: Developers',