<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def run(self):
 """ Run the event loop for the interface. This starts the interaction. """

        # Make sure everything is in sync, before starting.
        self.sync_with_prompt_toolkit()

        def pre_run():
            # Start in navigation mode.
            self.application.vi_state.input_mode = InputMode.NAVIGATION

        # Run eventloop of prompt_toolkit.
        self.application.run(pre_run=pre_run)