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: appointments_vaos_v2_list_request_spec.rb
    path of file: ./repos/vets-api/modules/mobile/spec/request
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

require 'rails_helper'
require_relative '../support/helpers/sis_session_helper'
require_relative '../support/matchers/json_schema_matcher'

RSpec.describe 'vaos v2 appointments', type: :request do
  include JsonSchemaMatchers

  before do
    allow_any_instance_of(VAOS::UserService).to receive(:session).and_return('stubbed_token')
  end

  let!(:user) { sis_user(icn: '1012846043V576341') }

  describe 'GET /mobile/v0/appointments' do
    before do
      Timecop.freeze(Time.zone.parse('2022-01-01T19:25:00Z'))
    end

    after do
      Timecop.return
    end

    let(:start_date) { Time.zone.parse('2021-01-01T00:00:00Z').iso8601 }
    let(:end_date) { Time.zone.parse('2023-01-01T00:00:00Z').iso8601 }
    let(:params)
    
      def fetch_appointments
        VCR.use_cassette('mobile/appointments/VAOS_v2/get_clinics_200', match_requests_on: %i[method uri]) do
          VCR.use_cassette('mobile/appointments/VAOS_v2/get_facilities_200', match_requests_on: %i[method uri]) do
            VCR.use_cassette('mobile/appointments/VAOS_v2/get_appointments_with_mixed_provider_types',
                             erb: erb_template_params,
                             match_requests_on: %i[method uri]) do
              VCR.use_cassette('mobile/providers/get_provider_200', match_requests_on: %i[method uri],
                                                                    tag: :force_utf8) do
                get '/mobile/v0/appointments', headers: sis_headers
              end
            end
          end
        end
      end