class Net::HTTP::Persistent

def expired? connection
  requests = Thread.current[@request_key][connection.object_id]
  return true  if     @max_requests && requests >= @max_requests
  return false unless @idle_timeout
  return true  if     @idle_timeout.zero?
  last_used = Thread.current[@timeout_key][connection.object_id]
  Time.now - last_used > @idle_timeout
end