Drop support for Python 3.6

Python 3.6 reached End Of Life a month ago.

Author: pgjones

.github/workflows/ci.yml

@@ -13,7 +13,6 @@ jobs:
       max-parallel: 5
       matrix:
         python-version:
-        - 3.6
         - 3.7
         - 3.8
         - 3.9

CHANGELOG.rst

@@ -5,6 +5,8 @@ Unreleased
 ----------
 
 - Added support for Python 3.10.
+- Drop support for Python 3.6, meaning the minimum supported version
+  is Python 3.7.0.
 
 
 1.0.0 (2020-11-22)

setup.py

@@ -31,15 +31,14 @@
     packages=find_packages(where="src"),
     package_data={'wsproto': ['py.typed']},
     package_dir={'': 'src'},
-    python_requires='>=3.6.1',
+    python_requires='>=3.7.0',
     license='MIT License',
     classifiers=[
         'Development Status :: 5 - Production/Stable',
         'Intended Audience :: Developers',
         'License :: OSI Approved :: MIT License',
         'Programming Language :: Python',
         'Programming Language :: Python :: 3',
-        'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: 3.7',
         'Programming Language :: Python :: 3.8',
         'Programming Language :: Python :: 3.9',
@@ -48,7 +47,6 @@
         'Programming Language :: Python :: Implementation :: PyPy',
     ],
     install_requires=[
-        "dataclasses ; python_version < '3.7'",
         'h11>=0.9.0,<1',
     ],
 )

tox.ini

@@ -1,9 +1,8 @@
 [tox]
-envlist = py36, py37, py38, py39, py310, pypy3, lint, docs, packaging
+envlist = py37, py38, py39, py310, pypy3, lint, docs, packaging
 
 [gh-actions]
 python =
-    3.6: py36
     3.7: py37
     3.8: py38
     3.9: py39