drop py36 support

Author: blink1073

.github/workflows/test.yml

@@ -15,7 +15,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest, windows-latest, macos-latest]
-        python-version: [3.6, 3.7, 3.8, 3.9, 3.10-dev, pypy-3.7]
+        python-version: [3.7, 3.8, 3.9, 3.10-dev, pypy-3.7]
         exclude:
           # pywin32 not available
           - os: windows-latest

pyproject.toml

@@ -13,4 +13,3 @@ strict_equality = true
 warn_unused_configs = true
 warn_unused_ignores = true
 warn_redundant_casts = true
-

setup.cfg

@@ -27,7 +27,7 @@ classifiers      =
 py_modules = jupyter
 packages = find:
 include_package_data = True
-python_requires = >=3.6
+python_requires = >=3.7
 install_requires =
     traitlets
     pywin32>=1.0 ; sys_platform == 'win32' and platform_python_implementation != 'PyPy'