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: base.rb
    path of file: ./repos/mongo-ruby-driver/profile/driver_bench/parallel/ldjson
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

require_relative '../base'

module Mongo
  module DriverBench
    module Parallel
      module LDJSON
        # The abstract base class for parallel LDSON benchmarks.
        #
        # @api private
        class Base < Mongo::DriverBench::Parallel::Base
          d
    
          def insert_docs_from_file(file_name, ids_relative_to: nil)
            next_id = ids_relative_to
            docs = File.readlines(path_to_file(file_name)).map do |line|
              JSON.parse(line).tap do |doc|
                if ids_relative_to
                  doc['_id'] = next_id
                  next_id += 1
                end
              end
            end