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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 unshare(self, con):
 """Decrease the share of a connection in the shared cache."""

        self._lock.acquire()
        try:
            con.unshare()
            shared = con.shared
            if not shared:  # connection is idle,
                try:  # so try to remove it
                    self._shared_cache.remove(con)  # from shared cache
                except ValueError:
                    pass  # pool has already been closed
        finally:
            self._lock.release()
        if not shared:  # connection has become idle,
            self.cache(con.con)