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: postgres_payload.rb
    path of file: ./repos/metasploit-framework/modules/exploits/windows/postgres
    
    the code of the file until where you have to start completion: ##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://gith
    
  def do_login(user=nil,pass=nil,database=nil)
    begin
      password = pass || postgres_password
      vprint_status("Trying #{user}:#{password}@#{rhost}:#{rport}/#{database}") unless self.postgres_conn
      result = postgres_fingerprint(
        :db => database,
        :username => user,
        :password => password
      )
      if result[:auth]
        report_service(
          :host => postgres_conn.peerhost,
          :port => postgres_conn.peerport,
          :name => "postgres",
          :info => result.values.first
        )
        return result[:auth]
      else
        print_error("Login failed, fingerprint is #{result[:preauth] || result[:unknown]}")
        return :noauth
      end