following along with Flask tutorial

weather/__init__.py

@@ -0,0 +1,26 @@
+import os
+
+from flask import Flask
+
+def create_app(test_config=None):
+    app = Flask(__name__, instance_relative_config=True)
+    app.config.from_mapping(
+        SECRET_KEY='dev',
+        DATABASE=os.path.join(app.instance_path, 'weather.sqlite'),
+    )
+
+    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('/hello')
+    def hello():
+        return "'Ello, Wurld!"
+
+    return app