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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 handle_error(self, callback):
 """ Called when an error occurs in an event loop callback. By default, sets the error view. """

        self.loop.log_error(callback)
        msg = "\n".join([
            "Exception in callback %r"%callback,
            traceback.format_exc()
        ])
        self.show_error(msg.encode('utf-8'))