add Dockerfile

.devcontainer/Dockerfile

@@ -0,0 +1,5 @@
+FROM mcr.microsoft.com/devcontainers/universal:2-linux
+
+RUN apt-get update && \
+    pip install django
+

.devcontainer/devcontainer.json

@@ -1,9 +1,14 @@
 // For format details, see https://aka.ms/devcontainer.json. For config options, see the
 // README at: https://github.com/devcontainers/templates/tree/main/src/universal
 {
-	"name": "Default Linux Universal",
+	"name": "Custom Linux Universal",
 	// Or use a Dockerfile or Docker Compose file. More info: https://containers.dev/guide/dockerfile
-	"image": "mcr.microsoft.com/devcontainers/universal:2-linux"
+	//"image": "mcr.microsoft.com/devcontainers/universal:2-linux"
+
+	"build": {
+        // Path is relative to the devcontainer.json file.
+        "dockerfile": "Dockerfile"
+    }
 
 	// Features to add to the dev container. More info: https://containers.dev/features.
 	// "features": {},