You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: redirects.rb
    path of file: ./repos/middleman/middleman-core/lib/middleman-core/sitemap/extensions
    
    the code of the file until where you have to start completion: require 'middleman-core/sitemap/resource'
require 'middleman-core/contracts'

module Middleman
  module Sitemap
    module Extensions
      # Manages the list of proxy configurations and manipulates the sitemap
      # to include new resources based on those configurations
      class Redirects < ConfigExtension
        se
    
        def render(*)
          url = ::Middleman::Util.url_for(@store.app, @request_path,
                                          relative: false,
                                          find_resource: true)

          if output
            output.call(path, url)
          else
            <<-END
              <html>
                <head>
                  <link rel="canonical" href="#{url}" />
                  <meta http-equiv=refresh content="0; url=#{url}" />
                  <meta name="robots" content="noindex,follow" />
                  <meta http-equiv="cache-control" content="no-cache" />
                </head>
                <body>
                </body>
              </html>
            END
          end