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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 simulate_async_event():
 """Simulate an asynchronous event."""

    scc.state = 'executing'
    def async_event(result):
        """All other asynchronous events or function calls
        returned from later steps will wait until this
        callback fires."""
        scc.state = result
        return 'some event result'
    deferred = Deferred()
    reactor.callLater(1, deferred.callback, 'done') # pylint: disable=E1101
    deferred.addCallback(async_event)
    return deferred