Modernize codebase

.flake8

@@ -0,0 +1,4 @@
+[flake8]
+ignore = E203, E266, E501, W503, E211, E731
+max-line-length = 88
+select = B,C,E,F,W,T4,B9

.github/workflows/ci-tests.yml

@@ -6,6 +6,10 @@ on:
   pull_request:
     branches: [ main ]
 
+concurrency:
+  group: build-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 jobs:
 
   tox:
@@ -16,9 +20,8 @@ jobs:
     strategy:
       matrix:
         py-ver-major: [3]
-        py-ver-minor: [6, 7, 8, 9, 10]
-        step: [unit]
-        #  step: [lint, unit, mypy]
+        py-ver-minor: [7, 8, 9, 10]
+        step: [lint, unit, mypy]
 
     env:
       py-semver: ${{ format('{0}.{1}', matrix.py-ver-major, matrix.py-ver-minor) }}
@@ -55,7 +58,7 @@ jobs:
 
       - name: Upload coverage to Codecov
         if: ${{ matrix.step == 'unit' }}
-        uses: codecov/codecov-action@v1
+        uses: codecov/codecov-action@v2.1.0
         with:
           fail_ci_if_error: true
 
@@ -66,12 +69,12 @@ jobs:
 
     strategy:
       matrix:
-        step: [lint-readme]
+        step: [pydocstyle]
         # step: [lint-readme, pydocstyle]
 
     env:
-      py-semver: 3.9
-      TOXENV: ${{ format('py39-{0}', matrix.step) }}
+      py-semver: "3.10"
+      TOXENV: ${{ format('py310-{0}', matrix.step) }}
 
     steps:
       - uses: actions/checkout@v2

.github/workflows/codeql-analysis.yml

@@ -2,27 +2,31 @@ name: "Code scanning - action"
 
 on:
   push:
+    branches: [main]
   pull_request:
+    branches: [main]
   schedule:
     - cron: '0 20 * * 5'
 
+concurrency:
+  group: codeql-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 jobs:
   CodeQL-Build:
 
     runs-on: ubuntu-latest
 
+    permissions:
+      security-events: write
+
     steps:
     - name: Checkout repository
       uses: actions/checkout@v2
       with:
         # We must fetch at least the immediate parents so that if this is
         # a pull request then we can checkout the head.
         fetch-depth: 2
-
-    # If this run was triggered by a pull request event, then checkout
-    # the head of the pull request instead of the merge commit.
-    - run: git checkout HEAD^2
-      if: ${{ github.event_name == 'pull_request' }}
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL

.isort.cfg

@@ -0,0 +1,6 @@
+[settings]
+multi_line_output=3
+include_trailing_comma=True
+force_grid_wrap=0
+use_parentheses=True
+line_length=88