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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 send(self, timeout=None):
 """Returns an event or None if no events occur before timeout."""

        if self.sigint_event and is_main_thread():
            with ReplacedSigIntHandler(self.sigint_handler):
                return self._send(timeout)
        else:
            return self._send(timeout)