code: def require_self(func, *args, **kwargs):
      
  
      try:
          __import__(package['name'])
      except ImportError:
          sys.stderr.write(
              "This component needs to be installed first. Run " +
              "`invoke install`\n")
          sys.exit(1)
      return func(*args, **kwargs)
docs: Decorator to require that this component be installed