The framework entry point is the Flask class in the flask.app module. Running a Flask application means running one single instance of this class, which will take care of handling incoming Web Server Gateway Interface (WSGI) requests, dispatch them to the right code, and then return a response.
WSGI is a specification that defines the interface between web servers and Python applications. The incoming request is described in a single mapping, and frameworks such as Flask take care of routing the call to the right callable.
The class offers a route method, which can decorate your functions. When you decorate a function with it, it becomes a view, and it's registered into Werkzeug's routing system. That system uses a small rule engine to match views with incoming requests, and will be described later in this chapter.
Here's a very basic...
