ci: two python versions

Jenkinsfile

@@ -1,20 +1,35 @@
 pipeline {
   agent none
   stages {
-    stage('Tests') {
+    stage('CPU') {
-      agent {
+      parallel {
-        docker {
+        stage('3.9'){
-          image 'python:3.9'
+          agent {
-          args '--user 0:0'
+            docker {
+              image 'python:3.9'
+              args '--user 0:0'
+            }
+          }
+          steps {
+            sh 'pip install pip --upgrade --progress-bar off'
+            sh 'pip install .[all] --progress-bar off'
+            sh './tests/test_examples.sh examples'
+          }
+        }
+        stage('3.8'){
+          agent {
+            docker {
+              image 'python:3.8'
+              args '--user 0:0'
+            }
+          }
+          steps {
+            sh 'pip install pip --upgrade --progress-bar off'
+            sh 'pip install .[all] --progress-bar off'
+            sh './tests/test_examples.sh examples'
+          }
         }
-
-      }
-      steps {
-        sh 'pip install pip --upgrade --progress-bar off'
-        sh 'pip install .[all] --progress-bar off'
-        sh './tests/test_examples.sh examples'
       }
     }
-
   }
 }