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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 post(self):
 """Create bucket."""

        with db.session.begin_nested():
            bucket = Bucket.create(
                storage_class=current_app.config[
                    'FILES_REST_DEFAULT_STORAGE_CLASS'
                ],
            )
        db.session.commit()
        return self.make_response(
            data=bucket,
            context={
                'class': Bucket,
            }
        )