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: spec_helper.rb
    path of file: ./repos/nanoc/nanoc-cli/spec
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

require_relative '../../common/spec/spec_helper_head_core'

require 'nanoc/cli'

require_relative '../../common/spec/spec_helper_foot_core'

Nanoc::CLI.setup

Class.new(Nanoc::Core::DataSource) do
  # fake
  identifier :filesystem

  def ite
    
  def postprocess(_site, _reps); end

  def rep_names_for(_item)
    [:default]
  end

  def action_sequence_for(rep)
    Nanoc::Core::ActionSequence.new(
      actions: [
        Nanoc::Core::ProcessingActions::Snapshot.new([:last], [rep.item.identifier.to_s]),
      ],
    )
  end

  def snapshots_defs_for(_rep)
    [Nanoc::Core::SnapshotDef.new(:last, binary: false)]
  end
end