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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def load_url(self, url, force=False, reload_seconds=0, callback_function=None):
 """ Starts loading a URL with an optional reload time in seconds. Setting force to True may load pages which block iframe embedding, but will prevent reload from working and will cause calls to load_url() to reload the app. """

        def launch_callback():
            """Loads requested URL after app launched."""
            should_reload = not force and reload_seconds not in (0, None)
            reload_milliseconds = (0 if not should_reload
                                   else reload_seconds * 1000)
            msg = {
                "url": url,
                "force": force,
                "reload": should_reload,
                "reload_time": reload_milliseconds
            }

            self.send_message(msg, inc_session_id=True,
                              callback_function=callback_function)

        self.launch(callback_function=launch_callback)