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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 offset(self):
 """ The offset of the event data object. :rtype: ~azure.eventhub.common.Offset """

        try:
            return Offset(self._annotations[EventData.PROP_OFFSET].decode('UTF-8'))
        except (KeyError, AttributeError):
            return None