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: user.rb
    path of file: ./repos/lita/lib/lita
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

require "redis-namespace"

require_relative 
    
      def create(id, metadata = {})
        existing_user = find_by_id(id)
        metadata = Util.stringify_keys(metadata)
        metadata = existing_user.metadata.merge(metadata) if existing_user
        user = new(id, metadata)
        user.save
        user
      end