Created a Github Workflow that checks files with black upon pushing t…

…hem to the repo

.github/workflows/presubmit.yml

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+name: Presubmit
+on: [push]
+jobs:
+  Presubmit:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/setup-python@v4
+        with:
+            python-version: '3.11'
+      - uses: actions/checkout@v3
+      - run: python3 -m pip install -r requirements-dev.txt
+      - run: ./check.sh

check.sh

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+#!/usr/bin/env bash
+
+CHANGED=0
+if [[ $# = 1 ]] && [[ "$1" = "--fix" ]]; then
+    if ! black --check . &> /dev/null; then
+        black . || exit 1
+        CHANGED=1
+    fi
+
+    if ! isort --check . &> /dev/null; then
+        isort . || exit 1
+        CHANGED=1
+    fi
+elif [[ $# -gt 0 ]]; then
+    echo "Usage: $0 [--fix]" > /dev/stderr
+    exit 1
+fi
+
+# if this fails with "black: command not found" you need to install black
+#    python3 -m pip install black
+echo Running black to check formatting...
+if ! black --check --diff --quiet .; then
+    echo "FAIL: formatting"
+    exit 1
+fi
+
+

requirements-dev.txt

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+black