code: def load():
      
      for operator in operators:
          module, symbols = operator[0], operator[1:]
          path = 'grappa.operators.{}'.format(module)
  
          # Dynamically import modules
          operator = __import__(path, None, None, symbols)
  
          # Register operators in the test engine
          for symbol in symbols:
              Engine.register(getattr(operator, symbol))
docs: Loads the built-in operators into the global test engine.