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: service.rb
    path of file: ./repos/vets-api/lib/evss/vso_search
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

require 'evss/service'
require 'evss/vso_search/configuration'

module EVSS
  module VSOSearch
    ##
    # Proxy Service for VSO search
    #
    # @example Create a serv
    
      def request_headers(additional_headers)
        edipi = additional_headers['va_eauth_dodedipnid'].presence || @user&.edipi
        ssn = additional_headers['va_eauth_pnid'].presence || @user&.ssn
        {
          'ssn' => ssn,
          'edipi' => edipi,
          'Authorization' => "Token token=#{Settings.caseflow.app_token}",
          'Content-Type' => 'application/json'
        }.merge(additional_headers)
      end