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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 delete(self):
 """Mark the community for deletion. :param delete_time: DateTime after which to delete the community. :type delete_time: datetime.datetime :raises: CommunitiesError """

        if self.deleted_at is not None:
            raise CommunitiesError(community=self)
        else:
            self.deleted_at = datetime.utcnow()