diff --git a/app/server/lib/ActiveDoc.ts b/app/server/lib/ActiveDoc.ts
index eaad7b3530..27dc7ff786 100644
--- a/app/server/lib/ActiveDoc.ts
+++ b/app/server/lib/ActiveDoc.ts
@@ -2830,7 +2830,7 @@ export class ActiveDoc extends EventEmitter {
 
   private async _makeEngine(): Promise<ISandbox> {
     // Figure out what kind of engine we need for this document.
-    let preferredPythonVersion: '2' | '3' = process.env.PYTHON_VERSION === '3' ? '3' : '2';
+    let preferredPythonVersion: '2' | '3' = process.env.PYTHON_VERSION === '2' ? '2' : '3';
 
     // Careful, migrations may not have run on this document and it may not have a
     // documentSettings column.  Failures are treated as lack of an engine preference.