ajout de l'index flaskr

flaskr/__init__.py

+import os
+from flask import ( Flask,
+Blueprint, flash, g, redirect, render_template, request, session, url_for)
+
+def create_app(test_config=None):
+    app = Flask(__name__, instance_relative_config=True)
+    app.config.from_mapping(SECRET_KEY='dev',  TESTING=True)
+
+    if test_config is None:
+        app.config.from_pyfile('config.py', silent=True)
+    else:
+        app.config.from_mapping(test_config)
+
+    try:
+        os.makedirs(app.instance_path)
+    except OSError:
+        pass
+
+    @app.route('/')
+    def home():
+        return 'Hello, World!'
+
+    return app