Fix error when getting page for invalid code

france/france_rsvp/web.py

@@ -37,6 +37,14 @@ def thanks():
 
 @app.route('/france/<code>', methods=['GET', 'POST'])
 def rsvp(code):
+    # Lookup guests from code
+    adults = None
+    children = None
+    try:
+        name, adults, children = get_name_and_replies(code)
+    except ValueError:
+        return render_template('form.html', error="Code invalide")
+
     error = None
     if request.method == 'POST':
         try:
@@ -49,14 +57,6 @@ def rsvp(code):
             record_reply(code, adults, children)
             return redirect(url_for('thanks'))
 
-    # Lookup guests from code
-    adults = None
-    children = None
-    try:
-        name, adults, children = get_name_and_replies(code)
-    except ValueError:
-        error = "Code invalide"
-
     return render_template(
         'rsvp.html',
         adults=adults,