Merge branch 'master' into srv_null_records

.github/workflows/main.yml

@@ -10,8 +10,7 @@ jobs:
     strategy:
       matrix:
         # Tested versions based on dates in https://devguide.python.org/devcycle/#end-of-life-branches, 
-        # with the addition of 2.7 b/c it's still if pretty wide active use.
-        python-version: [2.7, 3.6, 3.7, 3.8, 3.9]
+        python-version: [3.6, 3.7, 3.8, 3.9]
     steps:
       - uses: actions/checkout@master
       - name: Setup python

requirements-dev.txt

@@ -5,4 +5,4 @@ pycodestyle==2.6.0
 pyflakes==2.2.0
 readme_renderer[md]==26.0
 requests_mock
-twine==3.2.0
+twine==3.2.0; python_version >= '3.2'