code: def execute(self, logical_form: str):
          
          if not hasattr(self, '_functions'):
              raise RuntimeError("You must call super().__init__() in your Language constructor")
          logical_form = logical_form.replace(",", " ")
          expression = util.lisp_to_nested_expression(logical_form)
          return self._execute_expression(expression)
docs: Executes a logical form, using whatever predicates you have defined.