code: def apply_single_tag_set(tag_set, selection):
      
      def tags_match(server_tags):
          for key, value in tag_set.items():
              if key not in server_tags or server_tags[key] != value:
                  return False
  
          return True
  
      return selection.with_server_descriptions(
          [s for s in selection.server_descriptions if tags_match(s.tags)])
docs: All servers matching one tag set.
  
      A tag set is a dict. A server matches if its tags are a superset:
      A server tagged {'a': '1', 'b': '2'} matches the tag set {'a': '1'}.
  
      The empty tag set {} matches any server.