diff --git a/.github/workflows/unit.yml b/.github/workflows/unit.yml
index 66c5761..fedbfc4 100644
--- a/.github/workflows/unit.yml
+++ b/.github/workflows/unit.yml
@@ -7,7 +7,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.6, 3.7, 3.8, 3.9, 3.10, 3.11, 3.12]
+        python-version: ['3.6.15', '3.9.18', '3.12.0']
     steps:
       - name: Clone repository
         uses: actions/checkout@v3
@@ -23,7 +23,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.6]
+        python-version: ['3.6.15']
     steps:
       - name: Clone repository
         uses: actions/checkout@v3