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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):
 """Delete a multipart object."""

        # Update bucket size.
        self.bucket.size -= self.size
        # Remove parts
        Part.query_by_multipart(self).delete()
        # Remove self
        self.query.filter_by(upload_id=self.upload_id).delete()