Improve output

taas_client/cli.py

@@ -24,8 +24,10 @@ def upload_file(
     ),
     url: str = typer.Argument("http://localhost:5000/testbook", envvar="TAAS_URL"),
 ):
-    modified = time.time() - notebook.stat().st_mtime
-    console.print(f"Last change: [bold]{round(modified)}s[/bold] ago")
+    modified = round(time.time() - notebook.stat().st_mtime)
+    sec = 'second' if modified == 1 else 'seconds'
+    suffix = ', [red]make sure you saved![/]' if modified >= 10 else ''
+    console.print(f"Last change: [bold]{modified}[/bold] {sec} ago{suffix}")
 
     files = {"file": open(notebook, "rb")}
     try:
@@ -67,7 +69,7 @@ def upload_file(
             print(":boom: [bold]Submission failed![/]")
         except:
             pass
-        typer.Exit(code=1)
+        raise typer.Exit(code=1)
 
     print(":mailbox: :heavy_check_mark: [bold]Submission successful![/]")