Add support for Python 3.10 (#3009)

Author: nateprewitt

.github/workflows/run-tests.yml

@@ -13,7 +13,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: [3.6, 3.7, 3.8, 3.9]
+        python-version: [3.6, 3.7, 3.8, 3.9, 3.10-dev]
         os: [ubuntu-latest, macOS-latest, windows-latest ]
 
     steps:

setup.py

@@ -54,6 +54,7 @@ def get_version():
         'Programming Language :: Python :: 3.7',
         'Programming Language :: Python :: 3.8',
         'Programming Language :: Python :: 3.9',
+        'Programming Language :: Python :: 3.10',
     ],
     project_urls={
         'Documentation': 'https://boto3.amazonaws.com/v1/documentation/api/latest/index.html',

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = py36,py37,py38,py39
+envlist = py36,py37,py38,py39,py310
 
 # Comment to build sdist and install into virtualenv
 # This is helpful to test installation but takes extra time