def delete(key)
      deleted = false
      pool = nil
      @mutex.synchronize do
        pool = @_sessions.delete(key)
      end
      if pool
        pool.shutdown!
        deleted = true
        HotTub.logger.info "[HotTub] #{key} was deleted from #{@name}." if HotTub.logger
      end
      deleted
    end
def delete(key)
      deleted = false
      pool = nil
      @mutex.synchronize do
        pool = @_sessions.delete(key)
      end
      if pool
        pool.shutdown!
        deleted = true
        HotTub.logger.info "[HotTub] #{key} was deleted from #{@name}." if HotTub.logger
      end
      deleted
    end
Deletes and shutdowns the pool if its found.