'Hook for subclass initialization. Called for each request.
A dictionary passed as the third argument of a url spec will be
supplied as keyword arguments to initialize().
Example::
class ProfileHandler(RequestHandler):
def initialize(self, database):
self.database = database
def get(self, username):
app = Application([
(r\'/user/(.*)\', ProfileHandler, dict(database=database)),'

def initialize(self):

    pass
