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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):
 """Close the pooled shared connection."""

        # Instead of actually closing the connection,
        # unshare it and/or return it to the pool.
        if self._con:
            self._pool.unshare(self._shared_con)
            self._shared_con = self._con = None