make index function more pythonic

zesje/__init__.py

 from os import path
 from os.path import abspath, dirname, isfile
+
+from werkzeug.exceptions import NotFound
 from flask import Flask
 from flask_basicauth import BasicAuth
 
@@ -7,8 +9,7 @@ from . import db, api
 
 static_folder_path = path.join(abspath(dirname(__file__)), 'static')
 
-app = Flask(__name__,
-            static_folder= static_folder_path)
+app = Flask(__name__, static_folder=static_folder_path)
 db.use_db()
 
 
@@ -23,7 +24,8 @@ app.register_blueprint(api.app, url_prefix='/api')
 
 @app.route('/')
 @app.route('/<file>')
-def index(file=''):
-    if not isfile(path.join(static_folder_path, file)):
-        file = 'index.html'
-    return app.send_static_file(file)
\ No newline at end of file
+def index(file='index.html'):
+    try:
+        return app.send_static_file(file)
+    except NotFound:
+        return app.send_static_file('index.html')