check python installation; disable space clearing step

.github/workflows/tests.yml

@@ -18,21 +18,26 @@ jobs:
       uses: actions/setup-python@v2
       with:
         python-version: ${{ matrix.python-version }}
-    - name: Delete huge unnecessary folders, and clean apt cache
-      run: |
-        rm -rf /opt/hostedtoolcache
-        rm -rf /usr/share/dotnet
-        rm -rf /opt/ghc
-        rm -rf "$AGENT_TOOLSDIRECTORY"
-        sudo apt-get clean
-      shell: bash
+    # - name: Delete huge unnecessary folders, and clean apt cache
+    #   run: |
+    #     rm -rf /opt/hostedtoolcache
+    #     rm -rf /usr/share/dotnet
+    #     rm -rf /opt/ghc
+    #     rm -rf "$AGENT_TOOLSDIRECTORY"
+    #     sudo apt-get clean
+    #   shell: bash
     - name: Print space
       run: df -h
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
         pip install -r requirements/requirements.txt
         pip install -r requirements/requirements.dev.txt
+    - name: Check python installation
+      shell: bash
+      run: |
+        which python
+        python --version
     - name: Test with tox
       run: tox
     - name: Run coveralls