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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 enqueued_time(self):
 """ The enqueued timestamp of the event data object. :rtype: datetime.datetime """

        timestamp = self._annotations.get(EventData.PROP_TIMESTAMP, None)
        if timestamp:
            return datetime.datetime.utcfromtimestamp(float(timestamp)/1000)
        return None