diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 0167d8f660a..7f5804df41a 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -30,6 +30,10 @@ jobs:
       uses: actions/setup-python@v1
       with:
         python-version: ${{ matrix.python-version }}
+    - name: Get full python version
+      id: full-python-version
+      run: |
+        echo ::set-output name=version::$(python -c "import sys; print('-'.join(str(v) for v in sys.version_info[:3]))")
     - name: Install and set up Poetry
       run: |
         python get-poetry.py --preview -y
@@ -39,7 +43,7 @@ jobs:
       uses: actions/cache@v1
       with:
         path: .venv
-        key: ${{ runner.os }}-venv-${{ matrix.python-version }}-${{ hashFiles('**/poetry.lock') }}
+        key: ${{ runner.os }}-venv-${{ steps.full-python-version.outputs.version }}-${{ hashFiles('**/poetry.lock') }}
     - name: Install dependencies
       run: |
         source $HOME/.poetry/env
@@ -62,6 +66,10 @@ jobs:
       uses: actions/setup-python@v1
       with:
         python-version: ${{ matrix.python-version }}
+    - name: Get full python version
+      id: full-python-version
+      run: |
+        echo ::set-output name=version::$(python -c "import sys; print('-'.join(str(v) for v in sys.version_info[:3]))")
     - name: Install and set up Poetry
       run: |
         python get-poetry.py --preview -y
@@ -71,7 +79,7 @@ jobs:
       uses: actions/cache@v1
       with:
         path: .venv
-        key: ${{ runner.os }}-venv-${{ matrix.python-version }}-${{ hashFiles('**/poetry.lock') }}
+        key: ${{ runner.os }}-venv-${{ steps.full-python-version.outputs.version }}-${{ hashFiles('**/poetry.lock') }}
     - name: Install dependencies
       run: |
         source $HOME/.poetry/env
@@ -94,6 +102,11 @@ jobs:
       uses: actions/setup-python@v1
       with:
         python-version: ${{ matrix.python-version }}
+    - name: Get full python version
+      id: full-python-version
+      shell: bash
+      run: |
+        echo ::set-output name=version::$(python -c "import sys; print('-'.join(str(v) for v in sys.version_info[:3]))")
     - name: Install and setup Poetry
       run: |
         python get-poetry.py --preview -y
@@ -103,7 +116,7 @@ jobs:
       uses: actions/cache@v1
       with:
         path: .venv
-        key: ${{ runner.os }}-venv-${{ matrix.python-version }}-${{ hashFiles('**/poetry.lock') }}
+        key: ${{ runner.os }}-venv-${{ steps.full-python-version.outputs.version }}-${{ hashFiles('**/poetry.lock') }}
     - name: Install dependencies
       run: |
         $env:Path += ";$env:Userprofile\.poetry\bin"