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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 close(self):
 """Releases the connection back to the pool. Once this method has been called the underlying ``raw`` object must not be accessed again. *Note: Should not normally need to be called explicitly.* """

        if not self._content_consumed:
            self.raw.close()

        release_conn = getattr(self.raw, 'release_conn', None)
        if release_conn is not None:
            release_conn()