```ruby
namespace :dev do
  desc 'Toggle development mode caching on/off'
  task :cache do
    if File.exist? 'tmp/caching-dev.txt'
      File.delete 'tmp/caching-dev.txt'
      puts 'Development mode is no longer being cached.'
    else
      FileUtils.touch 'tmp/caching-dev.txt'
      puts 'Development mode is now being cached.'
    end

    FileUtils.touch 'tmp/restart.txt'
  end
end
```

Create tmp folder if not present
user
```ruby
namespace :dev do
  desc 'Toggle development mode caching on/off'
  task :cache do
    FileUtils.mkdir_p('tmp')
  
    if File.exist? 'tmp/caching-dev.txt'
      File.delete 'tmp/caching-dev.txt'
      puts 'Development mode is no longer being cached.'
    else
      FileUtils.touch 'tmp/caching-dev.txt'
      puts 'Development mode is now being cached.'
    end
    
    FileUtils.touch 'tmp/restart.txt'
  end
end
```
assistant