OPS-69105 proper command for python > 3.6

manifests/pyvenv.pp

@@ -36,10 +36,31 @@
   include ::python
 
   if $ensure == 'present' {
+    $python_version = $version ? {
+      'system' => $facts['python3_version'],
+      default  => $version,
+    }
+
+    $python_version_parts = split($python_version, '[.]')
+    $normalized_python_version = sprintf('%s.%s', $python_version_parts[0], $python_version_parts[1])
 
-    $virtualenv_cmd = $version ? {
-      'system' => "${python::exec_prefix}pyvenv",
-      default  => "${python::exec_prefix}pyvenv-${version}",
+    # Debian splits the venv module into a seperate package
+    if ( $facts['os']['family'] == 'Debian') {
+      $python3_venv_package="python${normalized_python_version}-venv"
+      case $facts['os']['distro']['codename'] {
+        'xenial','bionic','cosmic','disco','stretch','buster': {
+          ensure_packages ($python3_venv_package)
+          Package[$python3_venv_package] -> File[$venv_dir]
+        }
+        default: {}
+      }
+    }
+
+    # pyvenv is deprecated since 3.6 and will be removed in 3.8
+    if (versioncmp($normalized_python_version, '3.6') >=0) {
+      $virtualenv_cmd = "${python::exec_prefix}python${normalized_python_version} -m venv"
+    } else {
+      $virtualenv_cmd = "${python::exec_prefix}pyvenv-${normalized_python_version}"
     }
 
     $_path = $::python::provider ? {