code: def session(self) -> SessionT:
          '''Return a new session.'''
          session = self._session_class()(
              connection_pool=self._connection_pool,
          )
          self.event_dispatcher.notify(self.ClientEvent.new_session, session)
          return sessiof session(self) -> SessionT:
          '''Return a new session.'''
          session = self._session_class()(
              connection_pool=self._connection_pool,
          )
          self.event_dispatcher.notify(self.ClientEvent.new_session, session)
          return session
docs: Return a new session.