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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 connection to memcached, if it is open. The next call to a method that requires a connection will re-open it."""

        if self.sock is not None:
            try:
                self.sock.close()
            except Exception:
                pass
            finally:
                self.sock = None