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: in_process.rb
    path of file: ./repos/aruba/lib/aruba/processes
    
    the code of the file until where you have to start completion: require "shellwords"
require "stringio"
require "aruba/processes/basic_process"
require "aruba/platform"

# Aruba
module Aruba
  # Platforms
  module Processes
    # Run com
    
      def start
        raise "You need to call aruba.config.main_class = YourMainClass" unless main_class

        @started = true

        Dir.chdir @working_directory do
          before_run

          Aruba.platform.with_environment environment.merge("PWD" => @working_directory) do
            main_class.new(@argv, @stdin, @stdout, @stderr, @kernel).execute!
          end

          after_run

          yield self if block_given?
        end
      end