Use python3 as the canonical command name course-wide (#104) (#105)

modules/04-getting-the-ai-out-of-the-browser/lab/start/README.md

@@ -15,11 +15,11 @@ This is the running example for **Module 1** (where you feel the copy-paste prob
 ## Run it
 
 ```bash
-python cli.py add "read module 1"
-python cli.py add "set up my editor"
-python cli.py list
-python cli.py done 0
-python cli.py list
+python3 cli.py add "read module 1"
+python3 cli.py add "set up my editor"
+python3 cli.py list
+python3 cli.py done 0
+python3 cli.py list
 ```
 
 Requires Python 3.10+ (it uses `list[Task]` style type hints). No third-party packages.

modules/04-getting-the-ai-out-of-the-browser/lab/start/cli.py

@@ -1,8 +1,8 @@
 """Tiny command-line front end for the demo task app.
 
 Run it:
-    python cli.py add "write the lesson"
-    python cli.py list
+    python3 cli.py add "write the lesson"
+    python3 cli.py list
 
 State is kept in tasks.json next to this file. It's intentionally minimal; the point of this app
 is to be a realistic-but-small thing you change with an AI, not a product.
@@ -31,7 +31,7 @@ def save(tlist: TaskList) -> None:
 def main(argv: list[str]) -> int:
     tlist = load()
     if not argv:
-        print("usage: python cli.py [add <title> | list | done <index> | count]")
+        print("usage: python3 cli.py [add <title> | list | done <index> | count]")
         return 1
 
     command = argv[0]

modules/04-getting-the-ai-out-of-the-browser/lab/verify.sh

@@ -71,7 +71,7 @@ echo "Running delete-command check with: $PY"
 
 # Delete the middle task (index 1 = "beta").
 if ! "$PY" cli.py delete 1 >/dev/null 2>&1; then
-  echo "FAIL: 'python cli.py delete 1' errored. Is the delete command wired up in cli.py?" >&2
+  echo "FAIL: 'python3 cli.py delete 1' errored. Is the delete command wired up in cli.py?" >&2
   exit 1
 fi