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: md5.rb
    path of file: ./repos/ferrocarril/mruby-gems/vendor/ruby/2.6.0/gems/rack-2.0.7/lib/rack/auth/digest
    
    the code of the file until where you have to start completion: require 'rack/auth/abstract/handler'
require 'rack/auth/digest/request'
require 'rack/auth/digest/params'
require 'rack/auth/digest/nonce'
require 'digest/md5'

module Rack
  module Auth
    module Digest
      # Rack
    
        def params(hash = {})
          Params.new do |params|
            params['realm'] = realm
            params['nonce'] = Nonce.new.to_s
            params['opaque'] = H(opaque)
            params['qop'] = QOP

            hash.each { |k, v| params[k] = v }
          end
        end