code: def best_match(supported, header)
      parsed_header = header.split(",").map { |r| parse_media_range(r) }
  
      weighted_matches = supported.map do |mime_type|
        [fitness_and_quality_parsed(mime_type, parsed_header), mime_type]
      end
  
      weighted_matches.sort!
  
      weighted_matches.last[0][1].zero? ? nil : weighted_matches.last[1]
    end
docs: Takes a list of supported mime-types and finds the best match
    for all the media-ranges listed in header. The value of header
    must be a string that conforms to the format of the HTTP Accept:
    header. The value of supported is an Enumerable of mime-types
  
       irb> best_match(["application/xbel+xml", "text/xml"], "text/*;q=0.5,*/*; q=0.1")
       => "text/xml"