add classifiers for py3.9 and py3.10

Author: sjanssen2

setup.py

@@ -20,6 +20,8 @@
     Programming Language :: Python
     Programming Language :: Python :: 3.5
     Programming Language :: Python :: 3.6
+    Programming Language :: Python :: 3.9
+    Programming Language :: Python :: 3.10
     Programming Language :: Python :: Implementation :: CPython
     Operating System :: POSIX :: Linux
     Operating System :: MacOS :: MacOS X