pip install mypy

Author: cclauss

.github/workflows/build.yml

@@ -20,7 +20,7 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip setuptools six wheel
-          python -m pip install pytest-cov -r requirements.txt
+          python -m pip install mypy pytest-cov -r requirements.txt
       # FIXME: #4052 fix mypy errors in other directories and add them here
       - run: python3 -m  mypy --ignore-missing-imports
            arithmetic_analysis