Test on 3.10 and list it as supported

Author: oschwald

.github/workflows/lint.yml

@@ -19,7 +19,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v2
         with:
-          python-version: 3.9
+          python-version: "3.10"
 
       - name: Install dependencies
         run: |

.github/workflows/test.yml

@@ -14,7 +14,7 @@ jobs:
         # We don't test on Windows currently as it appears mocket may not
         # work there.
         platform: [ubuntu-latest, macos-latest]
-        python-version: [3.6, 3.7, 3.8, 3.9]
+        python-version: [3.6, 3.7, 3.8, 3.9, "3.10"]
 
     name: Python ${{ matrix.python-version }} on ${{ matrix.platform }}
     runs-on: ${{ matrix.platform }}

setup.cfg

@@ -12,14 +12,15 @@ universal = 1
 disable = duplicate-code
 
 [tox:tox]
-envlist = py36, py37, py38, py39, mypy
+envlist = py36, py37, py38, py39, py310, mypy
 
 [gh-actions]
 python =
     3.6: py36
     3.7: py37
     3.8: py38
-    3.9: py39, mypy
+    3.9: py39
+    "3.10": py310, mypy
 
 [testenv]
 deps =

setup.py

@@ -40,6 +40,7 @@
         "Programming Language :: Python :: 3.7",
         "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
+        "Programming Language :: Python :: 3.10",
         "Programming Language :: Python",
         "Topic :: Internet :: Proxy Servers",
         "Topic :: Internet",